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

TTRfan · Super Guru

Refurbishing another 2006 TTR250 - January 2014

Maniot · Veteran Member

Never boring Brian.....and full of great info!

buffalo4 · Veteran Member

Waiting for more Brian, Great stuff

j180 · Senior Member

You sir are a brave and knowledgable man. That's a bit more than my limited spannering skills would manage. Looking forward to seeing the updates.

TTRfan · Super Guru

Thank you guys - you asked for more so here it is! Quite a lot has happened recently despite a very slow start on this bike toward the end of November 2013.

Following on the engine theme, after carefully checking that the big and little ends were in good order, a new piston was fitted.

If you are doing this work yourself, make sure you cover the crankcase because I can guarantee that, if you don't, you will lose one of the circlips down there and they are hard to find and remove - don't ask how I know disbelief

Piston and barrel 001.jpg

Followed by a new base gasket. Fit the dowels in the crankcase to hold the gasket in place.

Piston and barrel 002.jpg

Don't forget to fit a new O ring to the base of the barrel.

Piston and barrel 003.jpg

Next, make sure the ring gaps are correctly positioned and the piston and barrel are nicely oiled up. Then slip the barrel over the piston. If I meet any resistance, I stop lift the barrel off and check all the rings are correctly in their grooves and try again. The piston usually slips in easily enough after a couple of goes! Then place the head gasket on. I am not sure why I haven't put the locating dowels in the top of the barrel at this stage to locate it properly confuse

Piston and barrel 004.jpg

Before tackling the cylinder head, I removed the clutch cover and adjusted the clutch.

Adjusting the clutch 1.jpg

And everything is now as it should be biggrin

Piston and barrel 012a.jpg

Fettling the cylinder head is next on the agenda!

TTRfan · Super Guru

OK so this is a little section on refurbishing and installing the head, and slotting the engine back in the frame

First off, strip out the head being careful to note the position of all parts removed, I use a little foam tray with cutouts to keep the valves, springs, buckets and colletts safely and in their right place.

Valves and head.jpg

Having got this far in stripping out the head, it makes sense to replace the valve stem oil seals. I remove the old ones using long nosed pliers.

Valves 006.jpg

These are the old seals and you will see that the ones from the exhaust valves (the two on the right of the pic) get a bit hot and harden up as a consequence.

Valves 007.jpg

Once the seals were out, I turned to the slightly tedious job of cleaning the valves and grinding them in. I put the valves in the electric drill and use a variety of scrapers etc to get all the carbon off. That on the exhaust valves can be particularly stubborn! I then use the drill with an oscillator to grind the valves in.

Valves 001.jpg

Having finished the grinding in process (and cleaned off every last grain of grinding paste!) I installed the new valve stem oil seals. Here is one ready to go in.

Valves 004.jpg

I find the easiest way to install the seals is to push them over the end of their valve and then push the end of the valve down until the seal pops into its new home.

Valves 009.jpg

The shims were Yamaha original as after-market ones are only available in increments of 0.05mm. Further proof to me that the engine hadn't been touched since new.

Valves 010.jpg

Having rebuilt the head on the bench and installed the camshafts and caps it was time to check and adjust the valve clearances using my laminated cribsheet smile

Valves 012.jpg

After nipping up the cam cover bolts, I use a thin spanner between the cam chain sprocket retaining bolts to turn the camshafts and put some pressure n the buckets to try and make sure that I am measuring the clearances correctly and there is no "slop" in the system.

The caps and camshafts are then removed and the head fitted after which they are put back on and a final check made to ensure the clearances are all still good.

Time then to finish off the engine with some paint before slotting it into the frame.

Engine complete 002.jpg

Engine complete 001.jpg

I had already cleaned up the engine mounting plates and bolts so it was a short job to get the engine back in its frame.

BEFORE:

Frame and wiring loom.jpg

AFTER:

Engine fitting 002.jpg

Just the carb, rear suspension, front forks and yokes, wheels and tyres, handlebars & switches, lights, indicators, seat, panels, tank, etc. left to do wink

Brian

TTRfan · Super Guru

I'm going to cut a long story short and let the photos do most of the the talking!

I cleaned up the front forks and fitted new Polisport gaiters, Venhill braided front hose, speedo head and cable, small indicators, grips, and front mudguard.

I rebuilt the speedo drive using new plain and tab washers and it all seems to be working fine.

Under the tank and seat 001.jpg

Oh yes, I cleaned up and fitted the switches as well. I will have to wait a bit longer to test them.

Under the tank and seat 002.jpg

I cleaned and put the carb through my ultrasonic cleaner and rebuilt it with new gaskets and fitted it to the TTR. I will only know if I did a good job when I get the TTR running and on the road.

Under the tank and seat 003.jpg

The rear suspension was rebuilt with new swing arm and linkage bearings and seals. Rear wheel, footpegs, chain & sprockets were fitted along with chain guards and lower chain guide. The sidestand was cleaned up and fitted together with its safety switch. Chain cover, footrests and gear lever also fitted.

Under the tank and seat 004.jpg

On the RHS, the rear brake lever was fitted along with the brake switch.

Under the tank and seat 005.jpg

Under the tank and seat 006.jpg

Under the tank and seat 008.jpg

The original ignition switch, helmet and steering lock with matching keys were fitted at an earlier stage in the build.

Under the tank and seat 009.jpg

The TTR came to me with a tatty after-market headlight so I replaced it with a new genuine Yamaha headlight surround and glass.

Under the tank and seat 010.jpg

Time to fit a new battery ready to check out all the electrical items wink

Under the tank and seat 007.jpg

Nearly there!

Brian

PS Everyone still awake?

Cubber · Super Guru

I'm amazed that you have all that energy, Brian.

Especially so directly after the Christmas celebrations.

It takes me all morning to get up, out of bed, breakfasted and dog walked. I'm then ready for bed!

Keep on with the good work, I'm enthralled if nobody else is.

Martyn

TT-R250M · Super Guru

Your rebuild threads are always worth a look Brian. It also helps keep things 'fresh' in the mind. Nice work as usual

Thanks for sharing Brian

Jarrah

TTRfan · Super Guru

Thank you guys - I will keep going then biggrin

A small job that makes a lot of difference is to clean and wire brush the silencer and respray in satin black. Like most TTR silencers, the stainless steel collar/guard on the rear was damaged and really let it down so I fitted one of our new guards - see here.

Exhaust stainless steel cover 001.jpg

Exhaust stainless steel cover 002.jpg

It now looks great.

I bead blasted the heat guard and sprayed it and that should be ready to fit as soon as the paint has cured.

Just remembered that I have to bleed the front brake after fitting the new Venhill hose and then it will nearly be ready to start up and take for a test run. If all OK then its on to the panels and tank.

Brian

Yuraku · Veteran Member

Superb, like all your rebuild articles.

You, Sir, are a perfectionist. Did you work for Yamaha by any chance? smile

Yuraku

TTRfan · Super Guru

Thank you Yuraku!

If any readers have a good memory, they will recall that I have not started up this TTR since I bought it. Today was the day!

I put on a spare tank and hit the start button. Didn't like the noise from the sprag on start up. The TTR started and ran perfectly so I let it warm up until it was off choke and then switched off. There was a tell-tale bang from the sprag which meant I was in for another job!

As I had just put in fresh oil I didn't want to drain and save it so took the tank off and laid the TTR on its side to replace the sprag.

Sprag 001.jpg

Stripping out the sprag was easy enough but my diagnosis of a worn sprag was confirmed when I found it jammed on the large starter gear.

Sprag 002.jpg

This occurs when a worn sprag clutch lets the engine kick back. I have had this before so have worked out a simple method to deal with it. I screw in a couple of bolts, put the gear in a padded vice and, using a long screwdriver, turn the sprag anti-clockwise the free it off.

Sprag 003.jpg

The sprag teeth/rockers were obviously worn so a new one has been fitted after first checking the boss on the large starter gear was undamaged and that the other two starter idler gears and their bearings and the starter pinion were perfect

Job done!

Sprag 007.jpg

Looking at the time the photos were taken, the whole job took 50 minutes from laying the TTR over to testing the new sprag. This time included freeing up the sprag.

Just the tank, rear mudguard and side panels to sort out now.

Brian

TTRfan · Super Guru

I remembered yesterday that I hadn't bled out the front brake after fitting a Venhill stainless front hose.

For a quick (and less messy) job I find you need two people but Trish was looking after granddaughter so no help available there cry

All that I needed was to have the brake lever and bleed nipple accessible at the same time confuse

After a bit of thought, I grabbed a spare pair of handlebars and fitted the brake reservoir/lever perch to it. I used some masking tape to attach the spare handlebars to the existing bars so that the reservoir was on the LH side of the bike and in easy reach. Didn't take long.

I was thinking that I was going to have to reverse fill the brake line from the caliper end using a syringe of brake fluid as it can sometimes be difficult to get some resistance at the lever.

However, I thought I would give the standard procedure a try first - nothing to lose. This is how I do it:

Put a clear plastic tube over the nipple - needs to be a really tight fit
Undo nipple (8mm spanner needed I think) and pull in lever
Catch waste fluid in a bottle, tin, or just lay loads of newspaper down - don't even think about re-using the old fluid!
Put a finger over the end of tube to seal it and release lever so that fresh fluid is sucked into the master cylinder rather than the old fluid going back in
Take finger off tube and pull in lever again
Put finger over end of tube and release lever
Repeat until no more air bubbles come out

I was lucky and this worked for me and had the advantage of flushing out the old fluid and replacing it with new.

I then had a good lever and re-fitted the reservoir to its correct position. No fluid spilled this time which is good as it will soon dissolve any fresh paint biggrin biggrin

Just the panels left to do then........

Brian

Cubber · Super Guru

Ingenuity won the day. confuse

What a start to a new year.

Brilliant bit of detection and repair - all very well chronicled and presented.

Thank you Brian.

Can you perform miracles with the weather now, please?

Martyn

TTRfan · Super Guru

Just for fun I fitted one of our polished s/s shorty pipes - I think it looked real good biggrin

Fladdem · Senior Member

Nice refurb, I love watching bikes get done up again to better than new mostly.

That header pipe is great, I have to get me one of those eventually.

TTRfan · Super Guru

Well, that one took a long time to finish disbelief

Anyways up, it flew through the MOT and was soon taxed and starting to be run in.

Here are some pics of the finished TTR.

LH side.jpg

RH side.jpg

Front right.jpg

Side view.jpg

It is now on its way to S France with a very happy new owner smile

Dave loading TTR.jpg

TT-R250M · Super Guru

Wow, really good job Brian (as usual).

I like the decals. aww

Jarrah

TTRfan · Super Guru

Thanks Jarrah wink

The decals actually look better in real life than in the pics. From Enjoy Mfg in the States. Fantastic quality.

Brian

Paul13 · Veteran Member

One day I can see myself buying one of your refurbished bikes.

Excellent job Brian, so impressed well done. blankstare

Flying Dodo · Veteran Member

A very happy Dave will be taking it out for exercise in the French countryside this weekend, it'll never look this clean again. And yes it looks (and rides) as good as it looks in the pictures. And Paul13 - you'll never get better anywhere. Thanks Brian.

Terrence R · Senior Member

Looks impressive. I'm just curious why you removed the s/s polished shorty header. Trying to keep it all OEM?

TTRfan · Super Guru

No - although it is very close to 100% OEM!

Because of the cost of manufacture I only keep a few shorty pipes in stock at any one time whereas I had the OEM header pipe there to be used. Also, I like to re-use as much of the original TTR as possible in the refurb - that's part of the challenge.

Brian

PS Thanks for your kind comments Dave! Good to have met you and shown you around some of our East Devon lanes. Shame to have got the TTR dirty though - especially as I found my power washer broken when I went to use it. Reason for that is in the pic below - the capacitor had totally melted and most of the sealant and insulation that should have been on the inside had made its way to the outside

Power washer 006.jpg

TT-R250M · Super Guru

TTRfan wrote:
Reason for that is in the pic below - the capacitor had totally melted and most of the sealant and insulation that should have been on the inside had made its way to the outside

Looks like those Chinese capacitors are not that good after all. wink

Jarrah

LRJ · Senior Member

I find it fascinating to see and read your rebuilding process, Brian. I almost wish that I lived in Britain so that I could buy one of your projects.

BM Steve · Guru

You know doing all the rebuild work on mine was quite time consuming at first.

it's the first bike rebuild for many years, but it's getting a bit faster and it's actually quite enjoyable once you get into the swing of it, fiddling and tinkering away

I have a really good sound system in the shed since I spend a fair bit of time there

So I just put on some music or an audio book and while away a couple of hours biggrin

BM Steve · Guru

I'll have to start taking some photo's soon of all the various things I have done

ttboof · Super Guru

BM Steve wrote:
You know doing all the rebuild work on mine was quite time consuming at first.
it's the first bike rebuild for many years, but it's getting a bit faster and it's actually quite enjoyable once you get into the swing of it, fiddling and tinkering away
I have a really good sound system in the shed since I spend a fair bit of time there
So I just put on some music or an audio book and while away a couple of hours

yeah I have a good set up in the shed and fiddling with the ttr is a great way of passing a bit of free time .it's autum here so the temps finally dropped below 30deg so more ttr bonding coming up

TTRfan · Super Guru

I have a cheap PC and monitor on the bench in my man shed. It uses Team Viewer to access my office PC and the interweb over a network which runs on the mains power cable using adaptors.

It allows me to take a break from the more tedious or difficult tasks to see what's happening on the forums and keep up to date on customers emails.

I also use it for internet radio as the reception for DABS radio is very poor in the workshop area as I used a lot of foil-backed insulation when building the workshop.

I can't work without constant background music wink

Brian