Trials tyre fitting problem

[puddytat]

Ive just purchased a trials (ish) bike & Ive noticed (apart from the valve locking nut being on the valve stem INSIDE the rim) that the tyre isnt sitting properly in the region of one of the tyre lock nuts. Ive let the tyre down & belted it around but it still aint right....
what gives?
Will I need to remove the tyre to sort it?

[Crasherfromwayback]

Ive just purchased a trials (ish) bike & Ive noticed (apart from the valve locking nut being on the valve stem INSIDE the rim) that the tyre isnt sitting properly in the region of one of the tyre lock nuts. Ive let the tyre down & belted it around but it still aint right....
what gives?
Will I need to remove the tyre to sort it?

You referring to one of the rim locks I assume? Can you loosen it off and push it in...or do you have it jammed between the bead and the rim?

[Ocean1]

From the rimlock comment I take it it's not a tubeless setup... so the most likely cause is the rimlock is either on the piss or it's the wrong size.

Just peel one side off and have a look to see if it's been sitting correctly, if it looks OK pull it out and check it's not damaged.

Edit: some people put a valve stem nut inside to help prevent the stem being pulled out when the tube "walks" inside the tyre. I didn't, but I never put one on the outside either, for the same reason.

[puddytat]

Cheers for that you two...yeah its got a tube & when theres no air in it i can push the rimlock in,but when i try to tighten it up or pull the
rimlock outwards it will not pull out as much as the other rimlock on the wheel....so i'd say its either of the two. I'll get hold of some tyre levers & have a squizz....
Interesting that bit on tube walk,you learn something everyday...

[Motu]

Is it a tubeless tyre you are fitting a tube into? Most modern trials tyres are tubeless, and you'll never get it to seat with a tube in - I've got a tubeless tyre on the front of my TLR200, in the 15 years it's been on 2 bikes that tyre has never seated. You need a tube tyre. With only one rimlock it must be a front wheel, wait until you do the rear with 2 rimlocks. And no valve stem nut - even with rimlocks, at 3 or 4psi it will still walk.

[Crasherfromwayback]

rimlock outwards it will not pull out as much as the other rimlock on the wheel....so i'd say its either of the two. I'll get hold of some tyre levers & have a squizz....
Interesting that bit on tube walk,you learn something everyday...

Is it a tubeless tyre you are fitting a tube into? Most modern trials tyres are tubeless, and you'll never get it to seat with a tube in - I've got a tubeless tyre on the front of my TLR200, in the 15 years it's been on 2 bikes that tyre has never seated. You need a tube tyre. With only one rimlock it must be a front wheel, wait until you do the rear with 2 rimlocks. And no valve stem nut - even with rimlocks, at 3 or 4psi it will still walk.

Think it's a rear wheel.

[puddytat]

Yup, its the rear wheel & its a 26yr old TLR250....just like the one you used to have Motu? The tyre's a mitchelin trials competition, tube type.
I shall forthwith remove the stem nut...

Did you gear yours down Motu? Im not doing "real" trials but it is to highly geared to loft the front easily...thinking to go to a 48 rear sprkt as theyre fucked & the chain is uber fucked.

[Motu]

Did you get a real TLR250, or that weird TLR250F ? A real TLR250 will work with standard gearing as they are a real trials bike....although 1st gear is used more often than a 2 stroke. The standard TLR200 is overgeared for trials, I think I have 11/50, and would like a 10 or 9 tooth sprocket, but I've given up, it's too gutless and I just thrash it in 1st everywhere. Dunno about the F model, it's a different engine I think. Idealy you should run in 2nd most sections, and the front should loft easily from an idle - but 4 strokes haven't got enough power, and also stall if 2nd is used in stuff like rocks. But a 4 stroke has traction - I use 1st and rev the shit out of it....it means I can't loft the wheel very well, but I just attack things like an MX rider and it seems to get through.

In a choice between power and handling I take handling every time. The TLR200 is a good handling twinshock, for the price. For the same price you can have a bad handling 2 stroke with plenty of power.

[puddytat]

Its a TLR250R....4 stroke
prolink rear,engine looks like a mid 80"s Xr cases bottom (no doubt the gearings different) with a single OHC head. will pick up the front in first o.k but its a tad overgeared for the tight bits and you do have to tackle things like mx or its out of its power. i'd like lower speed but higher revs.
Handlings awesum, will turn on a dime & suspension is adequate now that the bone dry linkages are greased & new oil in the forks (10wt)
Thought I might try a 46 or 48 tooth rear next (43std) & its got a 12 on the front so id try a 14 next maybe?

[Motu]

I'm not sure what those engines were based on, I thought it was the 4 valve XR200 engine, but apparently not. The TLR200 and 250 are based on the XR200 engine. You just have to accept the lack of power with a 4 stroke and hit things hard, using momentum and the better traction - throttle off and it'll stall, so work the throttle hard, on and off, on and off. A 2 stroke trials bike takes advantage of the lack of engine braking and uses the heavy flywheels to push it over things with the throttle shut...and no wheelspin.

Go for a 10 on the gearbox, you could use 2nd in easy stuff and hill climbs, but in rocks or other slow stuff just use 1st and keep the revs up to stop stalling.

[puddytat]

I have heard that those motor were built specially for the jap market & consequently are a prick to get parts for...
So you reckon just a 10 toothon the front & the standard 43 or 10 tooth & a larger rear as well?
Been fanging around the gullies this arvo, what a hoot
Cheers for that Motu