This may have been asked before.

I have heard that some riders have modified TLR frames to steepen the steering head angle by cutting and lengthening the frame top tube under the tank. The obvious place to do this is near the front between the headstock and the gusset plate. If anyone has done this, how much did they insert ( I have heard 5 or 6 mm being suggested ), how simple was it to do and did it produce the expected result? The other modification has been covered before which is to move the footrests back and down, again any experiences on this would be welcome, thanks.

Contact TY Offroad, Colin - he has done the steering mod to a 250, as have others. It's not very scientific - cut the frame say three quarters through the top tube where you suggest, then run the bike into the wall to move the wheel back the desired amount, say half an inch. This opens up a slight V in the tube where you cut it which is just welded over with a bit of plate. This is the easiest/quickest way of bringing the front wheel back.

He is also having bolt on kits made for the 250 to lower/move back the footrests which will save any welding direct to the frame

Haven't got his number to hand but if you search Google or whatever under TY Offroad (maybe all one word, not sure) you will get the website with contact details.

This may have been asked before.

I have heard that some riders have modified TLR frames to steepen the steering head angle by cutting and lengthening the frame top tube under the tank. The obvious place to do this is near the front between the headstock and the gusset plate. If anyone has done this, how much did they insert ( I have heard 5 or 6 mm being suggested ), how simple was it to do and did it produce the expected result? The other modification has been covered before which is to move the footrests back and down, again any experiences on this would be welcome, thanks.

Mine broke in half right under the tank (a weak design flaw) and I added reinforcements (I recommend this) but I have not changed the head angle (but think it might be a good mod). You have to be careful this frame steel is very soft and flexible.

BTW, how did lowering the pegs work?

I can tell you many good mods for this bike.

The question is: why steepening the steering angle ( reducing the fork inclination )? In my opinion it is an unuseful modify. Classic bikes had very good frames that were a good compromise between maneuvrability and stability. Some, like the first MAR , were very short and turned very strict, then in the last 70 bikes frames moved toward stability (my fantic 240 doesn't turn like the MAR). When the riding tecnique began to lift the rear wheel to turn it was discovered that a closer fork inclination eases the lifting. So: if you ride with a classical riding tecnique it is much much better a classic frame, more pleasant to drive and effective too. Only if you lift the rear wheel to turn you need a closer angle but you also need a modern rear suspension, a good front brake, an a engine weighting more onwards and 10 kg less, all things you don't have on a classic trials bike. And then: classic bikes must be ridden not improved, if you want a more performing bike you must choose a more modern one (many late '80 bikes are really well performing and really cheap). I apologize for my weak english!!!