A forum for owners of Yamaha TTR250 trail and enduro bikes!

Members Login
Post Info TOPIC: Simons 350 build


Senior Member

Status: Offline
Posts: 153
Date:
Simons 350 build
Permalink  
 


I've renamed this thread so that I've got a single place to put all my questions and updates about my 350 build. 

~~~~~~~~~~

Making slow progress on my 350, got the top end of this morning and was peering in at the crank. Does this look like a normal amount of blueing that one might expect from the heating of the crank for a press fit assembly? The engine was running and sounding fine before disassembly, so I'm going that there's nothing untoward about this, but wanted to check with the experts...

20201120_100205_copy_763x1612.jpg



-- Edited by Padowan on Friday 20th of November 2020 10:17:41 AM



-- Edited by Padowan on Friday 20th of November 2020 02:45:11 PM

Attachments
__________________


Super Guru

Status: Online
Posts: 8282
Date:
RE: Blueing of crank
Permalink  
 


Nowt to worry about Simon - most have bluing to some degree or another. As long as you have no up and down play on the big end or bluing or scoring of the little end you are OK wink

Good to see progress being made! Can't wait to get my 350 run in but not keen enough to take it out in today's rain cry

Brian



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

Great stuff. No up and down, there's a small amount of side to side, but I assume that's normal clearance.

The only thing that's really slowing me down at this point is a lack of boxes to arrange all the removed parts into, did too good a job clearing rubbish out of the garage!

__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Sideways play (unless excessive) is not a problem as it is needed to keep the piston and crankshaft alligned through its stroke.

The big strong veggie boxes from your nearest supermarket (with a layer of newspaper in the bottom) are ideal wink



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

I found some crates my wife had in the shed for storing vegetables from the allotment! Lined with card and now full of bits. Knocked up a clutch holder, but now I've hit a stumbling block on the other side as I don't have a puller for the flywheel. I've tried the rear axle, but can't seem to get enough leverage to tighten the axle and pop the taper. I also tried fitting an blind bearing puller and slide hammer, but was concerned I'd only be pulling it out by a single thread and might damage it. Will have to order one in.

20201120_141859.jpg20201120_141840.jpg20201120_141819.jpg



Attachments
__________________


Super Guru

Status: Online
Posts: 8282
Date:
Simons 350 build
Permalink  
 


Clever clutch holder!

That engine looks very clean.

Can you put some pipe over the axle stop to get extra leverage? Also don't be afraid to give the end a healthy knock to maybe jar the taper free wink

Otherwise, I got a puller here you can borrow Simon - "Click and Collect" - so all legal. I can leave it on the foorstep for collection. Don't want you being held up!



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Super Guru

Status: Offline
Posts: 2430
Date:
Permalink  
 

Good work so far, loving the clutch holderbiggrinbiggrin



__________________

totallyttrs.com

 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

While I try to sort out getting hold of a flywheel puller I thought I'd tackle a couple of other jobs on the list.

One nicely helicoiled exhaust stud hole.

20201120_174000_copy_686x986.jpg



Attachments
__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

Well that was harder than expected to get the flywheel off. Couldn't get adequate aligned leverage from using the rear axle, so ordered in a puller. I prefer 2 part pullers as the smaller inner pusher has a finer pitch thread, so ultimately a stronger push for a given rotation. After finally taking delivery of the puller this morning I set to work. Screwed in the puller and started winding in the inner. Nothing, a bit of rotation, but flywheel stuck fast. On removing the puller it was clear I was simply driving the inner into the crankshaft - the downside of a 2 part puller when the shaft has a tapered hole!

20201201_105643_copy_477x1008.jpg

To rectify the situation I found a suitable sized countersunk bolt to fit into the shaft, to give the puller something to push against. 

20201201_105656_copy_477x1008.jpg

Another go with the puller and off it popped with a bang. Needed more effort than I would have thought, but then again its cold today, so things will likely be on the tight side!

20201201_105702_copy_477x1008.jpg

Not a lot left to remove before I can split the cases now. 



-- Edited by Padowan on Tuesday 1st of December 2020 11:14:02 AM

Attachments
__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Well done Simon! Good thinking on using the countersunk boltsmile

I also had the same issue as you with a two-part puller which I destroyed and went in the bin. I now use a solid one and am lucky enough to have a windy gun and the flywheels always pop right off.

The standard Yamaha ones Steve sells are pretty good - see here

Good to get your updates biggrin



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

I've also got a windy gun, which did a great job of driving the tool into the shaft!

__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

And we're in! 20201201_135118_copy_1612x763.jpg



Attachments
__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

All the gubbins out and organised. Now to send the cases off to have the opening enlarged.

20201201_172107_copy_763x1612_copy_763x1121.jpg

Bearings are all Koyo, would that be original, or Brian, can you remember if you've been in this engine before? 

20201201_172057_copy_763x1612_copy_1000x763.jpg

 

 



Attachments
__________________


Super Guru

Status: Offline
Posts: 1123
Date:
Permalink  
 

Bearings are Koyo from the factory I believe. Are you going to replace them? If not, they need sealing off or removing - you will never clear the machining swarf from behind them otherwise.
Well done with that flywheel - harder than it should be! (Gorillagrip Sussex? )

__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

I think that while I'm in this far, it makes sense to not scrimp and replace the bearings (and seals). The current ones all feel lovely, so it seems a shame, but like you say, swarf will get everywhere. Although there is small part of me that is thinking that it'll only be soft aluminium swarf...

__________________


Super Guru

Status: Offline
Posts: 2430
Date:
Permalink  
 

Just remove them before machining, I replaced all mine, but didn't really need it no



__________________

totallyttrs.com

 



Super Guru

Status: Offline
Posts: 1123
Date:
Permalink  
 

Padowan wrote:

I think that while I'm in this far, it makes sense to not scrimp and replace the bearings (and seals). The current ones all feel lovely, so it seems a shame, but like you say, swarf will get everywhere. Although there is small part of me that is thinking that it'll only be soft aluminium swarf...


 Soft aluminium swarf will still bu@@er up your starter sprag and oil pump! Cleanliness is next to godliness

I covered mine in thick polythene sheet stuck down with silicone sealant, but if you've got a hot air gun  (or an understanding partner who doesn't mind the smell of 10W40 with the sunday roast) they're not too hard to remove.



__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

Shhh. Don't tell the missus...

20201202_120607.jpg

Getting the cases nice and clean, then I'll pop them in the oven to try to drop the bearings out.

 

What are people doing with the starter idler and clutch shaft roller bearings are people replacing those too? 



Attachments
__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Padowan wrote:

What are people doing with the starter idler and clutch shaft roller bearings are people replacing those too? 


I didn't replace mine and don't think Steve did either. 

I was really tempted to re-use all my internal bearings coz they all seemed good but I had bought new ones and, as I am not intending to rebuild any more TTR engines, I thought I had better use them! 

That said, the AllBalls main bearings are cheap enough and I think they should probably be replaced as a matter of course.

I am racking my brains to think of anyone ever posting on here having suffered a bearing failure. I did once replace a worn transmission output shaft bearing (the one the sprocket fits on) as the seal had failed and had let some grit or dirt in. I would think that is the bearing that does most work in the whole gearbox.

Who are you getting to bore your cases?

Brian

PS Great progress wink



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

Not decided yet on who to bore them out. I had some head/cylinder work done on the BMW GS a couple of years back by the guys up at Exeter Engineering who were very professional. Knowing that Dave Massam has done it before and will know how best to jig them up, I'm tempted to give him a call.

__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Padowan wrote:

Bearings are all Koyo, would that be original, or Brian, can you remember if you've been in this engine before?  


I honestly can't remember Simon disbelief

Other than when fitting a big-bore kit, the only reason I would have split the cases would have been to replace the gearchange shaft as often owners leave the gearchange lever loose and it kills the splines. 

 



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

In the oven, let's see how many drop out...

20201202_144907.jpg



Attachments
__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Make sure you have really good gloves on Simon! Most of mine fell out just by banging the cases on a block of wood wink



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

6 of them are out, after 30 mins in the oven and a gentle tug with the slide hammer. Mains are holding fast, will leave them in longer and have another go. Got some very good gloves, don't worry!

__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

The nice thing about the mains is there are some convenient gaps in the casting to tap them out with a punch from the outside biggrin



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

7 out, one main stuck fast, even after ~60mins at 190C. Was reluctant to tap them out from the back as you'd not have a central aligned pull and might damage the seat as you 'wobble' the bearing out...



-- Edited by Padowan on Wednesday 2nd of December 2020 08:03:13 PM

__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

Last one out after another stint in the oven and some persuasion with a punch and percussive implement. Having put the bearings through the washer and ****ting one out, they'll all be getting replaced. At least the cases are now ready to go off somewhere.

Hopefully I can clear the smell from the kitchen before the wife comes home!

__________________


Super Guru

Status: Offline
Posts: 2430
Date:
Permalink  
 

Blame Brian, I did biggrin



__________________

totallyttrs.com

 



Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Padowan wrote:

Hopefully I can clear the smell from the kitchen before the wife comes home!


Our pizzas that night were disgusting - they tasted of burnt WD40 disbelief



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Guru

Status: Online
Posts: 950
Date:
Permalink  
 

i like your style brian plenty of banter all good my pal

__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

So after a long delay and all sorts of lockdown restrictions, distractions and procrastinations on my side, I finally found some time to take the cases to an engineering shop for then to open them out to take the larger cylinder. Barum Engines, turned them around super quickly considering they said they were chockablock when I dropped them off. Collected them this morning, all seems in order and I'm ready to start reassembly (after a thorough clean)

20210607_165728_copy_477x1008.jpg20210607_165752_copy_477x1008.jpg

 



Attachments
__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

Having now given everything a decent wash and blow dry, the first task will be to get all of these in, probably tomorrow, after a day in the freezer. 20210607_201753.jpg



Attachments
__________________


Super Guru

Status: Offline
Posts: 1123
Date:
Permalink  
 

Well done Simon. Progress at last!
Don't forget to check there is clear space between the starter motor and back of the barrel before the final build - the fins there are too long out of the mold so they need filing back. Hopefully I did it before I dispatched it! (Can't tell from your pic)
Good luck!

__________________


Super Guru

Status: Offline
Posts: 2430
Date:
Permalink  
 

Good work matey

How much did barums charge you? they did mine (think I paid forty odd quid) and a customer with the 350 kit was asking if they could do his.

 



__________________

totallyttrs.com

 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

They charged £60, and despite being very busy and me telling them I was in no rush, they turned them around within the week.

__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Good to see that you can make progress now Simon smile



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Super Guru

Status: Offline
Posts: 2430
Date:
Permalink  
 

Padowan wrote:

They charged £60, and despite being very busy and me telling them I was in no rush, they turned them around within the week.


 Gone up a bit, but still good value. A customer in France was quoted £crazy money, think he has sent it to Barums now



__________________

totallyttrs.com

 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

mossproof wrote:

Well done Simon. Progress at last!
Don't forget to check there is clear space between the starter motor and back of the barrel before the final build - the fins there are too long out of the mold so they need filing back. Hopefully I did it before I dispatched it! (Can't tell from your pic)
Good luck!


 Thanks Simon,

The cylinder appears to have had the fins filed, so we should be good, but I'll do a dry fit before starting properly, just to be sure.

20210608_084646.jpg



Attachments
__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

ttr steve wrote:
Padowan wrote:

They charged £60, and despite being very busy and me telling them I was in no rush, they turned them around within the week.


 Gone up a bit, but still good value. A customer in France was quoted £crazy money, think he has sent it to Barums now


I also had a very high quote from another engineering shop, they were talking 4h+ of labour at £50/hr to jig it all up, and get the bore diameter just right, centred, perpendicular etc. When I queried, they were talking about thermal expansion and heat transfer requirements of the dissimilar metals, which are fair comments if this was a highly tuned small clearance race engine, but I think perhaps engineering overkill for a 20yr old air cooled tractor-donkey-bike! 



__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

That's 6 bearings in. For the remaining 2, the supplied bearings have lip seals on both sides, I've read about removing a seal, but not sure if that should be both seals, in/outboard seal only and whether the same applies to both the remaining bearings...

20210608_134103.jpg



Attachments
__________________


Super Guru

Status: Offline
Posts: 1123
Date:
Permalink  
 

I think one of the bearings which retains a seal is on a shaft which has an oil feed down the centre and out through the case, in which case the seal prevents pressure loss through the ball race. Unfortunately I can't remember which is which. Have you got photos of what came from where?

__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

To the best of my recollection the only bearing that retained an oil seal was the one arrowed in the photo below (93306-00320?). The seal goes on the "blind" side.

There are loads of photos on my 350 build thread here if you need any references.

5th Feb 2020 3a.jpg

 



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Super Guru

Status: Offline
Posts: 2430
Date:
Permalink  
 

That one costs a small fortune from Yamaha



__________________

totallyttrs.com

 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

I took Mossproofs advice and had a look at what I took out - why didn't I think of that! Both the bearings that came out have a single seal installed, so presumably those sealed sides go into the bind-side of the case, I have installed likewise.



-- Edited by Padowan on Wednesday 9th of June 2021 09:25:16 AM

__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

So how hard should I have to whack the crankshaft to get it seated in the main bearing? Both the bearing/case and the crankshaft are at room temperature so I could chill down the crank in the freezer, but I don't recall disassembly requiring really heavy tw@ttage to get the crank out. Am I missing a trick somewhere?

__________________


Super Guru

Status: Online
Posts: 8282
Date:
Permalink  
 

Is it just the clutch side that is tight or both?

My recollection is that the clutch side can be tight enough to require pulling the crank through the bearing by using a big socket as a spacer and tightening up the crank end nut to pull it through. Will try to find photo later.

I wouldn't recommend using a hammer wink

Brian



__________________

Exeter, Devon, UK

http://www.ttr250.com  - The one and only dedicated TTR250 FAQ! 
 

TIP: For easy viewing bookmark the "Recent Posts" view - http://ttr250.activeboard.com/p/recent/ 



Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

Excellent. Thanks Brian, why didn't I think about pulling it on! With a combination of the old bearing and several sockets, I was able to use the flywheel bolt to pull it home. (plus I put the crank on the freezer for a couple of hours). Onwards!

 

Edit, actually I had to do it twice as the con rod was in the wrong position first time! 



-- Edited by Padowan on Thursday 10th of June 2021 09:31:09 PM

__________________


Super Guru

Status: Offline
Posts: 1123
Date:
Permalink  
 

A job that's worth doing is worth doing twice
I use a hot air gun to warm the case to make things a bit easier. Glad you got there in the end.
BTW, the barrel fins have been trimmed so you should be ok.

__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

OK. That's it for tonight. Innards in, cases sealed and bolted together and new seals fitted.

Gubbins in:

20210610_214040.jpg

I've used Drei-Bond with great success on the engine cases of my old GS. 20210610_214130.jpg

Bead of sealant20210610_214720.jpg

Cases fitted together and torqued up. 20210610_215159.jpgBead of sealant squeezing out nicely

20210610_220346.jpg

New seals20210610_220357.jpg



-- Edited by Padowan on Thursday 10th of June 2021 10:16:31 PM

Attachments
__________________


Senior Member

Status: Offline
Posts: 153
Date:
Permalink  
 

So having got a lot of the stuff in the RH side of the case following the exploded diagrams in the service manual, I have a washer left over. It's not the one that hides under the shift fork. Is there a washer under the first circlip before the kick start idler gear? The kick start mechanism isn't in my manual so I can't be sure, but this would fit as it'd take any lateral play out of the countershaft...

20210611_182416.jpg



-- Edited by Padowan on Friday 11th of June 2021 06:29:12 PM

Attachments
__________________
1 2  >  Last»  | Page of 2  sorted by
 
Quick Reply

Please log in to post quick replies.



Create your own FREE Forum
Report Abuse
Powered by ActiveBoard