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350cc Big Bore Kit for the TTR250 - updates and gossip!
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X 2
;)

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Can't wait to see how it goes 

When Yamaha took the 550 out to 600 it got more torque  but was a bit slower due to the recipricating mass the 350 should pull well 



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Got my crankshaft rebuilt with one of Steve's conrod kits in the optimistic hope that it'll run Simon wink

Another bit of TTR porn:

Rebuilt crankshaft.jpg



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Found any time for the engine this last week Simon?

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I hope to be taking my crankcases for machining tomorrow, I know Simon has also been crazy busy, so don't worry we will both be road testing very soonsmilesmile



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Crankcases are now in the machine shop, so getting a bit closer to road testing time.smilesmile



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What are you having done to the crankcase exactly?



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Steve's crankcases are being bored to take the bigger diameter sleeve as Simon had done - his photo below after boring.

Bored crankcases.JPG



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Ok, ok, i should have guessed. Fingers crossed for successful tests. I for one can't wait!!



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Engine's in the bike. Just deciding on jets for the carb, but sadly won't be done this w/end as I'm at the Adventure Travel Film Festival.
Keep the faith brothers, won't be long,
Simon.

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Ladies and Gentlemen, the world now contains 1 living breathing running Yamaha TT350R!!!!

After a few setbacks like delaminated inlet stub, and dropping a 48 jet into a black hole in my garage, tonight I took the plunge and gave it a go. Filter housing filled with oil, primed a bit on the kickstarter, got my brother to hold a camera, kicked the dogs out, twice, span her over without plug a bit, wound in a plug, 3 twists of the throttle and she went first go.

Yeeehaaa!

Hopefully we can get the footage into this thread, and if we do, I apologize in advance for the quality - just an old camera not an i-thing.

Twice round the field and the smoke cleared quickly (lots of oil in the bore from assembly). First impression: Oooh, this feels nice

There's a bit of pop on the overrun. Could be air leaking somewhere, could be mixture. I will be running with an air/fuel ratio (AFR) gauge, and dyno'ing when I've done some running in. It's too dark to play now.

Can't really believe it's finally happened!

Time for a beer. Cheers!

Simon.



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Awesome..;)

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Excellent new Simon!

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Epic!!

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Well earn't beer for sure, congrats!!

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Amazing, congrats!



-- Edited by robs on Thursday 16th of August 2018 07:40:22 PM

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Here it is, youtubed by ex MrsTTR Trish, many thanks Trish - you may have found yourself a job

Footage of 5th gear wheelies coming later, when it's run in a bit

www.youtube.com/watch

That was genuinely the first spin. The smoke from the assembly oil was gone before the first lap of the field. I'm not showing much emotion - shock I think!

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What a stupendous reward for you Simon, I bet you're over the moon. thumbsup.gif

Martyn



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Fantastic achievement Simon. I have been quietly following and can't wait to hear your real world experience riding it. One day, I will rebuild my 1993 OE and this surely must be the way to go. Well done.

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This is awesome news.. patiently waiting for the Dyno results..
Si

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100 miles and no smoke or nasty bangs!

Currently running standard exhaust and airbox, twinair filter. 48/142 jets (needle standard position)
AFR meter indicating rich at idle (10 - 11) #46 pilot jet on order. Mid range richness (11 - 12) should be sortable by dropping the needle. WOT about right (12.5ish) Leaning it all out might actually not be desireable for tractability/"feel", but you never know 'till you try...
Makes you ride like a hooligan on the street, so that's a positive
Pics of the Lambda sensor and wide band AFR meter:

 

P1010808.JPG

P1010810.JPG



-- Edited by mossproof on Wednesday 22nd of August 2018 10:55:22 AM

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Nice work Simon

If you feel like that on the bike (hooligan) then that is sounding very positive, as extra power is the holy grail and fingers crossed you have found it! Fantastic work and looking forward to testing minesmilesmile



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In case anyone's wondering what I'm waffling about with air/fuel ratios, or why I'm not putting more miles on the 350 'till my #46 pilot jet arrives, here's some light reading on the subject, and as you can see from the pic above, 11.9:1 at tickover is a little low.

www.safrtool.com/SAFR-AFR-values.asp



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Jase at Lee Motorcycles in Ledbury loading the 350 onto his dyno:

Worn out Heidenau K60 is the closest I've got to a road tyre!

 

P1010824.JPG



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First dyno results are in, and I must admit to feeling disappointed and encouraged in equal measure! With my 325 dyno session some years ago (and on a different dyno) yielding 27.4hp @ 7900rpm, and 20.1ftlbs @ 6600, I was really hoping to top this, even though that was with a Motad end can and enlarged snorkle in the airbox.

Well, put baldly, the 350 gave us 23.7hp @ 7720, and 20.1ftlbs @ 5100. (All standard air and exhaust system), which frankly I was not expecting since the bike picks up much better than my 325 and feels stronger all through the range.

At this point, Chris FBRConcepts is saying "told ya so", and having spent today staring at the graphs, and being happy that fueling is appropriate, it would appear that airflow is holding us back.

Looking at the power printout (and comparing with the standard 250 tested earlier), we get peak power at 6670rpm, but then it plateaus (flattens out biggrin) for a further 2000rpm before tailing off. The 250 has a constant rise 'till virtually the end of it's rev range, which is a more normal pattern of events, and suggests to me that something is stopping the 350 output from continuing to rise, and if fuelling is still ok, then that "something" is air restriction, either by physical constriction or turbulence.

I also notice the 350 was comfortable to rev some 700rpm more before Jase cut the throttle.

Are you all glazing over yet? confuse

Anyway, here's the power plot. Red line 350, blue line 250.

 

TTR Power.jpg

 

 

 



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Don't go away, I'm not done yet!

Turning to the torque curve, it becomes clear why the bike pulls so well. A lovely steep and smooth increase from low down, fairly broad peak, coming in 600rpm sooner than the 250.

TTR Torque.jpg

 

What I take from all this is that there is much room for further improvements. While I was initially disappointed that it isn't just a quick "bolt on this barrel and all your troubles are over" type of thing, realistically that was never going to happen with such a radical alteration to the bike's dynamics. Next move is to bolt on some different exhaust options. If the afr ratios change significantly, that would suggest to me that air is flowing better, then a bigger snorkle in the airbox, and finally possibly some porting and head work. I think larger valves and major head mods are beyond what I really want to do, and likewise I don't want to get into bigger carbs. I've only put 350 miles on the bike so far (so you might suggest maybe she's not yet run-in?) but there's a #2 being built this week, and as the miles rack up, I expect there will be some kits coming available as confidence builds.

In short, I think this may be a good base for some massive improvements (it's already a massive improvement in real-world riding and my main disappointment is that the electrodyno doesn't reflect what my arsedyno can feel!)

For the record, this test was done with standard airbox containing Twinair foam filter, standard exhaust system. Carb jets are 46/142 and the needle is down 1 notch (leaner than std) Gearing 14/49 tooth. Over the 350 miles so far, I've calculated approximately 65mpg (imperial gallon 4.54 litres) and that has involved lots of blipping up and down through the rev range I can tell you!

All constructive comments welcomesmile



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Not so Simple is it Simon? fight.gif

I have no doubt whatsoever that your efforts will not be in vain, Rome wasn't built in a day and all that.

What you have achieved is remarkable, if it were me I'd have a box of bits in front me, maybe hot, oily and stinking but totally useless.

Don't give up because your hard work will produce something that none of us has - a bike they have BUILT all on their own, by themselves - and it works. number1.gif

Martyn



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The seat of the pants results can be good & bad, I used to modify & fiddle with my bikes back in my early 20's ( I raced scrambles as they were called back then ) was also a motor mechanic as well, the hours & money I spent with modifications were over the top but the bikes were not as good as what we have today.

I used to spend hours testing with the seat of the pants in both engine & bike setup & sometimes I would loose my way, pretty common to get confused after a while.
The seat of the pants result tells me my TTR is better with the Staintune muffler but I might be wrong, these days I just leave the WRR standard engine wise & adjust the dampening & fit bars & levers etc. The WRR feels quicker than the TTR & the lads I ride with say I am a lot quicker on the WRR, it can be hard to tell by the seat of the pants feel but in this case it's correct.

Do what ever you are happy with but the painful fact is with engine modifications you will be chasing your tail, as you modify one bit it will have a flow on effect & so on, you will get there in the end but with a few why are I doing this.

I'm lucky in the fact I have both a TTR & WRR so I can choose on the day if I want the slightly quicker bike, Yamaha spent a lot of money building the WRR engine & is bloody good, uses less fuel & provides more power & this is what you are up against & good luck for the project. You are a better man than me putting the hours into this, I just don't have the time to do such, perhaps when I quit work in a couple of years.

Cheers Terry

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I reckon you have done well. You got 23.7 hp with a standard exhaust and standard airbox. So the motor is pretty strangled.

I got 23 hp with airbox mods (snorkel removed) GYTR pipe and TTR's only shorty header, 2mm overbore, ported head higher compression. And that's a fun bike to ride.

But 263 cc has nowhere near the torque of your 350cc bike.

You will definitely see substantial gains by uncorking. The 250's standard are fairly choked up and give great improvements in power with derestricting. ie. - just airbox and pipe mods.

The 350 should show even better gains, that bigger piston is trying to draw a lot of air through the carb.. P.S. I'm thinking of a Mikuni TM33 Pumper for mine, that would rock on yours.

I'm glad you have dynoed the 350 standard, now let it breathe and lets all see the real potential.

I can foresee about 30 hp!! ;)



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Thanks for the support and encouragement. It's been a long but interesting journey and it's not over yet!

Martyn, that warm glow from starting the engine for the first time and not have it spitting bits of piston all over the garage door is still with me

Comparisons with the WR R are always going to be there, although they're very different bikes (which is probably why you still own both Terry?) Peak torque from the 350 is already higher than the WR though, and comes in MUCH lower down the rev range making it a very flexible engine that doesn't need revving. If I can eventually hit the 30hp that the WR puts out, with a more tractable and torquey low-mid range, that will be the engine Yamaha SHOULD have put in the WR R (watercooled of course) to make it an excellent dual sport instead of an enduro bike with an extra gear.

I'd love to see the results of a TM33 pumper conversion, although the smaller intake on the TK promotes torque I believe, and that is really what makes the bike rideable even though the horsepower figure is what draws the attention.

Back to the workshop...


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It will be good to see what the main choking point is..
I'm guessing first exhaust then carb then airbox and lastly head porting..
Si

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I too am an avid TTR250 owner/lover and I've been seeking TTR250 performance upgrades.

… I've been watching this thread with some excitement for about four months now. I live in the USA and I use my TTR as my main enduro/trail bike - woods only use, not tagged to be street legal. ( Dirt use is my focus! ) I use to race hare scrambles and enduro. When I raced Hare Scrambles, my bike then was a very solid reliable Yamaha TT350. When I ran Enduro, moved up to a 1996 KTM 620EX/C. 

Wow… the TTR250 - the perfect combination for me today - now I’m 58 and I simply ride trails. ( At a very elevated, fast pace, I should add ) Being motivated to ride fast, my 2003 TTR250 has been the subject of quite a bit of performance enhancing thought and modification. 

I'm VERY EXCITED to see a 350cc upgrade kit coming .. I check this thread regularly for the most current updates and look for the opportunity to purchase a kit in the near future.  

Here is what I've done to improve my TTR250 ( and I look forward to adding another 100cc !! ) :

I’ve added a lightened flywheel. I had it shaved down and there was 1 lb 3 oz. removed. This simple move works amazingly well... this one modification alone helps transform the engine into something much more fun to ride. It’s now zippy, very responsive.

I recently added a 2003 WR250F muffler section. The stock WR250F muffler really uncorked my TTR250, adding much more power. Way more than the stock muffler, and more power than that YZR600 ?? titanium something something crotch rocket street muffler I had started out with. 

I’ve also added 2003 YZ250 USD forks & clamps. Again! Another super improvement over the stock 1980's style TTR250 conventional forks.

I've bumped up the seat hight using a old TTR125 seat foam directly on top of the low slung TTR250 seat foam, then stretched a gripper seat cover over the sandwich. WOW> This trick makes the bike feel taller and easier to ride in the woods! I can really corner like a bandit now that I can slide up close to the filler cap and actually stay there. It's also very easy to stand up on now. This is a cheap and effective modification that I highly recommend to others. 

I've cut out almost the entire top of the air box for better breathing, and I’ve added a "twin air" air filter. 

I’ve been working slowly with changes so as to get them all dialed in correctly for the best performance. In the ready room, are  sitting a pair of custom ground cams that I had made this summer, and also a 74mm WISCSO piston set. Right now, I'm waiting to see what the 350cc kit turns out to be like before I work on adding only 1mm to the bikes cc size. I also have a brand new 34mm OSO flat slide carburetor for use later on. The stock carburetor works very well, but I’m prepared to use something better maybe bigger if I need to.

The performance cams however; I am VERY eager to install. As far as I can tell, there is only one company advertising on the web ( Web Cams in the USA ) that offers performance cams for the TTR250 engine. They offer two different grinds; one is a mid to top end cam grind, the other is a low down torque cam grind. What I had ground for me was a grind that is very close to the Web Cams mid to top end cam profile - I used Web Cams advertised specs to go by while I was searching for a custom cam grinder who could make a set for me. The regrind Web Cams TTR250 cams run $550.00. I went looking for any and all performance reviews but could not find any. There has been only one set of each grind purchased from them. I know this because I asked Web Cams how many they have sold! So, I'll take it that this one subject is uncharted ground. I have also learned that Kibblewhite offers high lift springs and retainer sets for a .410 lift cam for the TTR250 engine. Interesting… no special cams yet there are performance valve springs and retainers available? I haven’t found anyone yet who has installed / have used high performance cams in a TTR250 engine. 

I feel that adding a nice performance cam set to a TTR250 with a 350cc upgrade should eventually make a huge difference in overall HP & torque numbers.

( Btw; I asked my grinder what the stock cam values were, and was told both cams are 300 lift. )

In case you’re interested, here's my new cam regrind details:

intake duration: 278 

Intake Duration at .050: 230 

Intake Lift: 320 

Intake valve clearance: 004 - 006

 

Exhaust duration: 278 

Exhaust duration at .050:  230

Exhaust lift: 320

Exhaust clearance: 006 - 008

Well… thanks for tolerating my comments. I just couldn’t read any more without shouting out with excitement; I’m pretty stoked to see a TTR250 350cc kit in the works! - TTR Keith

PS: Attached are a few pictures of my ever evolving, well loved, project TTR250! ( And the modified WR250F muffler )



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Welcome to the forum, Keith. handshake.gif

What kept you? You should have shouted well before now. A lot of riders could benefit from all the alterations/modifications/upgrades you've done to your TTR. biggrin

You seem to have worked wonders on your own already and here's hoping that you get more help here.

Martyn



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Thank you, Martin!

I surely don't want to steal any thunder that the 350cc upgrade kit  is making ... but for sure, I'm eager to learn about / willing to try it / definitely into this subject!

 



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Welcome Keith. Nice to hear some more enthusiasm for the TTR AND the 350.

My knowledge of cam modification is practically zero, and there's hardly ever been a mention on the forum that I can remember - someone once said they were going to fit some they saw advertised, then never posted on the subject again. Your experiences will be interesting to hear - maybe start a "cam mods thread" to save it getting lost in the 350 one, when you've got them in and running. Have you done any head porting/gas flowing?

The TTR engine was used in a road bike for a while, can't remember which one just now - maybe that was the reason for the aftermarket springs?

Nice usd fork conversion too. Love the gold rims.


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Thank you for the compliments! I love the gold rims also. I'm a fan of the old ISDE look. I've even created a full gas tank sticker that reflects this theme and the first application of it didn't go so well. ( it lasted exactly one week )

I do have a few new ideas on how to get them to stick permanently, though. 

A special thread about the custom ground cam set is a great idea. I will do it as soon as I have some news to report, but you can always send me an Email if you have any questions before I get to making a post. (  bre66@windstream.net  )

I check this Email address a few times a week for important and private messages. ( or you can send me a head's up that you've sent a message here at this page? ) 

I did take the time to disassemble the wheels and have the rims powder coated in a "Ferrari gold" color. I also painted the hubs a "Yamaha" blue. I wish now that I had power coated those at the same time though, as the paint doesn't like to stick to the hubs. Oh well... MORE WORK AHEAD! 

About the head, and porting it: nope, not yet. I want to get the cams in first. Then find out what the jetting might be... then go forward from there. But I have a very knowledgable moto-X mechanic friend who knows quite a large amount about how to do it right. I'll be getting with him on that soon, also.

I'm wondering right now if anyone on this list may have an extra set of white raid 250 or white TTR250 side panels and a rear fender? I'd love to score some. 

Here is what my custom made fictional Yamaha ISDE fuel tank decals look like. Sitting next to my TTR250 is my old trusty friend of 20 + years now. ( the monster bike my friends are afraid of to ride ) A 1996 ISDE KTM 620 EX/C. Lordy! What a great bike that is! When Dick Burlson saw this a few years ago while at a local riding park, he got pretty excited and proclaimed that he wished he never sold the one he had! It's the dirt bike standard that I measure all of my dirt rides by. I'm working hard to get my TTR250 up to that bikes feel and pull and I think I'm getting close, as far as I can tell. The TTR's beginning to handle like the KTM, and I am hopeful that soon it will have arm wrenching power that I can use to abuse the chain with! Seriously though, I'm not ashamed to admit it, I love both bikes equally the same. Hahahah! blankstare 

You can see the old Yamaha titanium muffler and original fork set in the photo. I wrapped the street bike muffler with a blue anodized aluminum foil sticker material and added FMF Ti 4.1 stickers to it to help fool any onlookers! 

To get those large YAMAHA stickers to stay mated to the tank, I'm going to make a plate cover wrap from thin aluminum sheeting. The fumes from the gas seeps through the plastic, and work to push decal stickers away via large gas bubbles between the plastic and the vinyl.

BRING ON THE BIG BORE 350cc!

 

 



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Fantastic work Simon

You should be proud of making a 350 kit that works so wellsmile Just finishing off your road testing? 

My Build has been a bit of a snails pace, turns out all my crankcase bearings have had it, as I do not know any history of the crankcases, I am going to replace them all cry Causing more delay. I hope to be putting it in the bike next weekend., as I am away on the TRF event in Hereford this weekend. (taking the wr250f)

Anyways keep up the excellent work.

Steve



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mossproof wrote:

Thanks for the support and encouragement. It's been a long but interesting journey and it's not over yet!

Martyn, that warm glow from starting the engine for the first time and not have it spitting bits of piston all over the garage door is still with me

Comparisons with the WR R are always going to be there, although they're very different bikes (which is probably why you still own both Terry?) Peak torque from the 350 is already higher than the WR though, and comes in MUCH lower down the rev range making it a very flexible engine that doesn't need revving. If I can eventually hit the 30hp that the WR puts out, with a more tractable and torquey low-mid range, that will be the engine Yamaha SHOULD have put in the WR R (watercooled of course) to make it an excellent dual sport instead of an enduro bike with an extra gear.

I'd love to see the results of a TM33 pumper conversion, although the smaller intake on the TK promotes torque I believe, and that is really what makes the bike rideable even though the horsepower figure is what draws the attention.

Back to the workshop...

Yes I keep the TTR because it is a good bike & different to the WRR, The WRR is very much like a 2T to ride, if only Yamaha had fitted EFI to the TTR & raised the HP

Terry


 



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Simon and Steve,
Once two bikes are built, you blokes can be the first two in the world to race each other on TTR350's!!!   



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Being an impatient chap (and it taking a little while for Steve's local 350 build to materialise wink),  I took the opportunity of doing a short via on my way to an electro-plating course near Burton-on Trent to pop in to see Simon and blag a ride on his 350.

I am really glad I did. I don't know why but I didn't expect the motor to sound as sweet as it did - perhaps it's the quality of the kit or a testament to Simon's spannering skills - I am sure we will find out when Steve's 350 is up and running biggrin

Anyways up, Simon trusted my lardy ass with the 350 and led me off through his farmyard and hundreds of suicidal free-range chickens (scary things that fly out across your path from nowhere evileye) to a large field (which I guess is his own personal playground) in which to test out the world's first TTR350. 

The field looked large until I started giving the 350 the beans when suddenly it seemed to shrink at an alarming rate!  The 350 truly has the torque that Simon mentioned and easily broke traction in the high gears from mid-throttle. Fantastic fun and perfect for trail riding where you need the power mid range.

Can't wait to (a) get Steve's 350 built and (b) get a kit of my own to build biggrinbiggrinbiggrin

Brian

PS I trusted Trish to take some video but, sadly, it is mostly of the ground - and no bikes apart from a tiny section which I will try and retrieve when I can get her phone off her long enough to transfer the footage onto my PC disbelief



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Fingers crossed Bri, we should be sorted for my build on Monday. Will be doing a full report on my trials and tribulations of how thing's can slow you down a bit (or a lot) I have been taking photos of all my work, so far smile



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TTR Keith wrote:

I too am an avid TTR250 owner/lover and I've been seeking TTR250 performance upgrades.

… I've been watching this thread with some excitement for about four months now. I live in the USA and I use my TTR as my main enduro/trail bike - woods only use, not tagged to be street legal. ( Dirt use is my focus! ) I use to race hare scrambles and enduro. When I raced Hare Scrambles, my bike then was a very solid reliable Yamaha TT350. When I ran Enduro, moved up to a 1996 KTM 620EX/C. 

Wow… the TTR250 - the perfect combination for me today - now I’m 58 and I simply ride trails. ( At a very elevated, fast pace, I should add ) Being motivated to ride fast, my 2003 TTR250 has been the subject of quite a bit of performance enhancing thought and modification. 

I'm VERY EXCITED to see a 350cc upgrade kit coming .. I check this thread regularly for the most current updates and look for the opportunity to purchase a kit in the near future.  

Here is what I've done to improve my TTR250 ( and I look forward to adding another 100cc !! ) :

I’ve added a lightened flywheel. I had it shaved down and there was 1 lb 3 oz. removed. This simple move works amazingly well... this one modification alone helps transform the engine into something much more fun to ride. It’s now zippy, very responsive.

I recently added a 2003 WR250F muffler section. The stock WR250F muffler really uncorked my TTR250, adding much more power. Way more than the stock muffler, and more power than that YZR600 ?? titanium something something crotch rocket street muffler I had started out with. 

I’ve also added 2003 YZ250 USD forks & clamps. Again! Another super improvement over the stock 1980's style TTR250 conventional forks.

I've bumped up the seat hight using a old TTR125 seat foam directly on top of the low slung TTR250 seat foam, then stretched a gripper seat cover over the sandwich. WOW> This trick makes the bike feel taller and easier to ride in the woods! I can really corner like a bandit now that I can slide up close to the filler cap and actually stay there. It's also very easy to stand up on now. This is a cheap and effective modification that I highly recommend to others. 

I've cut out almost the entire top of the air box for better breathing, and I’ve added a "twin air" air filter. 

I’ve been working slowly with changes so as to get them all dialed in correctly for the best performance. In the ready room, are  sitting a pair of custom ground cams that I had made this summer, and also a 74mm WISCSO piston set. Right now, I'm waiting to see what the 350cc kit turns out to be like before I work on adding only 1mm to the bikes cc size. I also have a brand new 34mm OSO flat slide carburetor for use later on. The stock carburetor works very well, but I’m prepared to use something better maybe bigger if I need to.

The performance cams however; I am VERY eager to install. As far as I can tell, there is only one company advertising on the web ( Web Cams in the USA ) that offers performance cams for the TTR250 engine. They offer two different grinds; one is a mid to top end cam grind, the other is a low down torque cam grind. What I had ground for me was a grind that is very close to the Web Cams mid to top end cam profile - I used Web Cams advertised specs to go by while I was searching for a custom cam grinder who could make a set for me. The regrind Web Cams TTR250 cams run $550.00. I went looking for any and all performance reviews but could not find any. There has been only one set of each grind purchased from them. I know this because I asked Web Cams how many they have sold! So, I'll take it that this one subject is uncharted ground. I have also learned that Kibblewhite offers high lift springs and retainer sets for a .410 lift cam for the TTR250 engine. Interesting… no special cams yet there are performance valve springs and retainers available? I haven’t found anyone yet who has installed / have used high performance cams in a TTR250 engine. 

I feel that adding a nice performance cam set to a TTR250 with a 350cc upgrade should eventually make a huge difference in overall HP & torque numbers.

( Btw; I asked my grinder what the stock cam values were, and was told both cams are 300 lift. )

In case you’re interested, here's my new cam regrind details:

intake duration: 278 

Intake Duration at .050: 230 

Intake Lift: 320 

Intake valve clearance: 004 - 006

 

Exhaust duration: 278 

Exhaust duration at .050:  230

Exhaust lift: 320

Exhaust clearance: 006 - 008

Well… thanks for tolerating my comments. I just couldn’t read any more without shouting out with excitement; I’m pretty stoked to see a TTR250 350cc kit in the works! - TTR Keith

PS: Attached are a few pictures of my ever evolving, well loved, project TTR250! ( And the modified WR250F muffler )


 Your bike is very simular to mine... even the same forks...

have you weighted it ?.... mines at 115kgs with 5 liters of fuel..

 

 

..



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 http://www.kiwibiker.co.nz

Bikes... 06 TTR250 / 09 XT660R / 1977 Montesa Cota 348 MRR / 1979 Montesa H6 125 Enduro...

E-mail  xtpete1@gmail.com



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ttr steve wrote:

Fingers crossed Bri, we should be sorted for my build on Monday. Will be doing a full report on my trials and tribulations of how thing's can slow you down a bit (or a lot) I have been taking photos of all my work, so far smile


I spent an enjoyable day with Steve today helping him with his 350 build. Starting from bare crankcases, we managed to get all the bearings and crankcase internals in and the crankcases buttoned back together plus fitting most of the clutch side components.

We ground to a halt when Steve discovered he was missing a couple of small kickstart components so they will be needed before much more can be done. Nevertheless, a good start and the rest won't take long once the parts arrive biggrin

I think Steve may have got away with heating the crankcase halves in the oven as he heated our lunchtime pasties afterwards and I am sure they smelt stronger than the WD40 wink

Despite heating the cases and freezing the bearings, only one dropped in and the rest needed some persuasion as Steve demonstrates in the photo below smile

Steve fitting bearings.jpg



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pug


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Brian hears one for you next time try a plumbers Arctic Spray Pipe Freeze kit next time get them screwfix or on the bay put bearing into a Styrofoam cup in a china mug cut a bit of Styrofoam to fit in top of cup spray the stuff into the cup leave for 60 sec take out and it should just drop into case that is at room temp or just put a blow torch passed over the case a time or two if its a cold day works for me. make sure you handle the cold spray and stuff with gloves or you be on your way to Hospital and they be trimming your fingers down a bit


Pug

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Steve does quite a bit of plumbing work so he probably had some of that on his van Pug no



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I see Steve is using 4GY cases with a breather in the case. Could be handy to increase crankcase breathing.
Going to use a later type clutch?

That's a good idea there Pug. Saves an overnight in the freezer!

Looking forward to #2 hitting the trails soon

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Ok

I think it is about time I did a bit of a report on my 350 kit.

First off, I find anything I do to the bike is hard work and seems that anything that can go wrong does!

I bought the crankcases in and found out that the bearings were not up to scratch, you could see marks inside the bearings where the balls run on and I decided to replace all the bearings. Glad I did as I found some very sharp and hard bits of metal hiding behind one of the bearings!

The good news is that most of the bearings are standard and I ordered Koyo ones from simply bearings, the next good news was that the all ballls ones I stock for the crank are made by Koyo smile

The bad news is that Mr Yamaha decided to put 2 bearings in there that are only available from him and boy did they cost a lot cry

I got all the bearings here and Bri told me to do the oven and freezer trick 

1.jpg

2.jpg

 

Why do my pictures always come out wrong? I even turned them in the original files and they are still wrong???? Straight now Steve Cubber

Anyway glad Lisa was not here to see what we was up to!

The next problem was that I have mislaid a couple of the kickers small parts, luckily they are cheap, not so lucky one is a back order item and may take a while to get here cry

I can crack on with the build though, as I have the barrel and piston to fit and the cylinder head has been given the once over and new shims fitted smile and even if not finished the kicker I can still get the engine in my bike.

Thanks to Bri for giving me the kick up the backside to start my build, I find it hard to find time to do this stuffcry

 



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