And so it begins, My IT250H Build

[Trokel510]

Other than the public holidays I am working through the Xmas break so don't have a lot of spare time for work on the bike but it is still coming along slowly but surely.


This motor came with the 2nd bike and according to the guy i bought it from it has had all new bearings and seals through the bottom end and also been re sleeved back to standard. Looking in the exhaust port it all looks brand new. One thing I noticed that I thought was a bit strange was that it is running a single ring piston so i was wondering, is that a common thing and are there any benefits?

So after a bit of cosmetic work on the motor here is how it all looks currently.

[80-85 husky]

looking the goods

[tony27]

Single ring piston could be out of a YZ, wouldn't expect it to maintain full compression for as long

[Trokel510]

Single ring piston could be out of a YZ, wouldn't expect it to maintain full compression for as long

Yeah sort of figured that, therefore probably not the best choice for an enduro bike which makes me wonder why they are even available like that. Does one ring yield that much better performance in the short term to make the shorter life worth it?

[BETRIC]

Troy use a 2 ring Wossner piston in the IT, I used a stainless steel shock pin and furrules from Moto Enduro UK on my IT , keep an look out for shock oil weeping from the shock hose as they are getting old now I had to replace mine recently, Sean at SOS Suspension replaced the hose on my shock.

[80-85 husky]

the single ring piston is for performance at cost of wear - mx. 2rings support piston for longer bore life = enduro.

[Trokel510]

Well all I can say is this bike has been a challenge and taken up huge amounts of my time but finally it looks like things are coming together and with a bit of luck i will kick it in the guts tomorrow and be rewarded with that beautiful 2 stroke sound.
Unfortunately due to being so busy i haven't had the time to do a detailed built update on a regular basis but here is some more pics of how it has progressed.

One of the most time consuming parts has been sorting out the exhaust. From both bikes I bought I had 2 different expansion chambers and mufflers, one of each (muffler/Chamber) seemed original but in poor condition and the other 2 were different and of unknown origin and none of them seemed to match up with the existing mountings.
Here is one of the mufflers

 

 

[Trokel510]

So I went in search of a new muffler and was thinking of buying a brand new DG but due to the expense as well as the thought that I would probably still have to modify it to match the different expansion chamber I ended up buying this second hand RMX250 muffler on ebay and modifying it to fit but at the same time still had to work out how the new side cover was going to mount up.

[VTR Vinduro]

 I new Ride for This Year  Vinduro Season  Troy ...

 You have done a  Good job ......

 VTR

[Trokel510]

 I new Ride for This Year  Vinduro Season  Troy ...

 You have done a  Good job ......

 VTR

Thanks.

Started it up last weekend and it seems to run pretty well and idles nice but haven't had a chance to ride it yet to see if it revs out properly. Also Still lots of little bits and pieces to finish off and have been a bit side tracked working on the XR600 to get it ready for Broadford so it hasn't progressed much since then.

Now for a few more pics 
As mentioned earlier the front end i used was from an early TT250 which was wider between the mounting pins on the lower triple clamp.



 I noticed this was also the case for the later K model front end I had so here is what I did to accommodate the H style headlight surround. .
 First I had to remove the original mounting pins which are pressed in. A pair of vice grips and brute force while twisting back and forth worked well here.



Then I drilled the holes a bit deeper and tapped them with a 6mm thread and made up an alloy plate with stainless bolts fitted to form the new mounting pins and bolted it all into place.