First Model TT350??

[shelpi]

sorry to butt in but I'm looking for a cylinder for a xt/tt 250 do you have one to spare? thanks

[Tex]

I rode the little XT250 in it's last event, the River Murray Trial near Mannum on Saturday. A great ride, but a lot of deep sand which really highlighted the 250's power deficiency. The paddock sections were also full of deep whoops, which showed the folly of trying to ride a simple trail bike in these types of events.

Jeez, I reckon the bloke on the 2 valve XT250 would have done it tougher! 

Tex

[80-85 husky]

my back hurts just thinking about it

[LWC82PE]

Nah i reckon this would have been a piece of cake for him. He finished the 24hr this year which was in very, very bad muddy wet windy conditions with only 40 solos finishing out of over 100 starters (huge list of DNF's). Just goes to prove you can finish on anything if you set your mind to it.

[Colin Jay]

Adam (the guy on the 2 valve) is a good rider and is deceptively fast on the old girl. The only time I have been quicker through a paddock section has been on the rare occasion that he had dropped it.

[shelpi]

sorry to butt in but I'm looking for a cylinder for a xt/tt 250 do you have one to spare? thanks

bump

[Colin Jay]

Sorry, No. I might be looking for one myself, as I have just measured the bore on the cylinder that I have and it is 4th OS and the corrosion would require a rebore to remove.

[GMC]

Beware over revving the TT 350, I held mine flat for too long during the 88 Mallee Rally and I had one of the cam shafts jump a tooth, took me ages to work out why it was running like shit, only worked it out after finding out a mates jumped both cams and his valves did a tap dance on the piston

[80-85 husky]

"Adam (the guy on the 2 valve) is a good rider and is deceptively fast on the old girl."

Impressive...imagine how fast he would be on a husky!

[FourstrokeForever]

Beware over revving the TT 350, I held mine flat for too long during the 88 Mallee Rally and I had one of the cam shafts jump a tooth, took me ages to work out why it was running like shit, only worked it out after finding out a mates jumped both cams and his valves did a tap dance on the piston

Would that be caused by a stretched timing chain or worn adjuster Geoff? Or is it the nature of the beast?

[Scuberdiver]

Another SA rider here i will be building up a tt350 as well over the coming summer have two in my shed 91and 94 have the 86 250 as well but its just a roller so thats the one i will be doing up  hope to do a couple of road trials next year on it  if all goes to plan  cheers jeff

[shelpi]

Sorry, No. I might be looking for one myself, as I have just measured the bore on the cylinder that I have and it is 4th OS and the corrosion would require a rebore to remove.

that's ok ive managed to get a cylinder on standard bore and needs to go to 1st oversize
yep mines on 4th and its worn, but when looking I found the std twin came bore is 73mm
and the std single came bore is 75mm so does anyone know if the single cam piston can go into the twincam if anyone has an old sohc piston I would be interested in it to do a comparison

[Nathan S]

Trusting my memory:
The SOHC piston has a big ugly hump in the middle to get the compression ratio up, and is quite different to the twin cam piston.

Pics on parts list may help to confirm or deny this.

[FourstrokeForever]

I had no luck finding a high comp piston for my 350. Stock is 9:1. With a few head mods and a 20 thou shave on the head and barrel I've managed to bump compression up to about 9:8. Now I just have to tune the carbies to the head and exhaust..... I hate twin carbies on single cylinder dirt bikes as they need to be removed to make any changes. Even worse that the TT secondary is a vacuum assisted main jet!

[shelpi]

Trusting my memory:
The SOHC piston has a big ugly hump in the middle to get the compression ratio up, and is quite different to the twin cam piston.

Pics on parts list may help to confirm or deny this.

thanks Nathan, will look into it, but would still like to have an old tt/xt single cam piston in my hot little hands please, just thinking Mill !