A TY175 is probably a fair bit better than a TL125. Less weight probably makes more of a difference for a newer rider than the power but you still need to have "enough".

Most of the time you don't need more power. But a small bike doesn't have any reserve and if you have to roll off and roll back on in a climb you may not have enough power to recover the lost momentum. If everything in the section goes as planned then the less powerful bike is just fine. A more powerful bike might get you into trouble by giving you more power when you don't need it, or it might allow you to pull out of something instead of stopping.

It is like riding a peaky first year CR125 around a motocross course and then hopping on a 400 Maico. An expert may be able to just as fast on either one (and I've seen fast guys ride a 125 in the 250 and open classes and do well on tight tracks) but a novice may have an easier time on the big bike with a broad and smooth powerband than they will trying to keep the 125 on the pipe.

I like heavy flywheel bikes. I wish I could get my KT250 to have as much flywheel as my Sherpa T had. But other people like a snappier power delivery to attack a section with. I like a big soft engine with lots of flywheel that lets me idle through and put my attention on steering instead of trying to keep the engine from stalling or being in the right gear.

If the trials you attend all have those "meet yourself around every turn" tight sections a TY175 or 123 Cota may be the ticket. If instead you have predominately long loose uphill climbs with entry and exit cards only and everything in between unmarked then a big bike might be "more perfect" than the little one.

Horses for courses.

cheers,

Michael

The Bob Gollner modified KT did have a far heavier flywheel, and as you rightly say this does tone down the power delivery of the KT, which could get less experienced riders into trouble.......................

It isn't so much the way the power is delivered as that seems pretty controllable on my bike. I'd like more flywheel because if I'm going along dead slow at minimum RPM sometimes hitting a rock or root can be just enough extra load to cause the bike to stall. I don't want to gear the final drive down to allow more RPM or to run a high idle. I wouldn't mind having better throttle control and the ability to better pay attention to everything going on in a section so as to be able to avoid the root or give a small whiff of throttle to get past that point. Having some more flywheel mass on the KT would let it run on "autopilot" a little more when in those extremely slow speed/RPM situations.

Maybe having had a lot of big thumpers (Matchless, BSA, Yamaha) has something to do with my preference for more flywheel. The 325 Sherpa T ran like my thumpers - smooth low end power and lots of flywheel. The KT has good power, it just is a bit "zingy" for my tastes. A flywheel weight (which I do intend to make) should help that.

cheers,

Michael

It isn't so much the way the power is delivered as that seems pretty controllable on my bike. I'd like more flywheel because if I'm going along dead slow at minimum RPM sometimes hitting a rock or root can be just enough extra load to cause the bike to stall. I don't want to gear the final drive down to allow more RPM or to run a high idle. I wouldn't mind having better throttle control and the ability to better pay attention to everything going on in a section so as to be able to avoid the root or give a small whiff of throttle to get past that point. Having some more flywheel mass on the KT would let it run on "autopilot" a little more when in those extremely slow speed/RPM situations.

Maybe having had a lot of big thumpers (Matchless, BSA, Yamaha) has something to do with my preference for more flywheel. The 325 Sherpa T ran like my thumpers - smooth low end power and lots of flywheel. The KT has good power, it just is a bit "zingy" for my tastes. A flywheel weight (which I do intend to make) should help that.

cheers,

Michael

I think the Gollner had a special wider ignition cover to allow 2lbs extra weight to be added to flywheel................. there are some details about the Gollner on the web somewhere.

I think the Gollner had a special wider ignition cover to allow 2lbs extra weight to be added to flywheel................. there are some details about the Gollner on the web somewhere.

There was a extra flywheel weight that bolted to the existing flywheel and a spacer casing with longer bolts, you could take the weight off and run standard if you wanted.

I have a bolt on weight in the garage somewhere no casing or bolts if mr moore would like it.