cleanorbust

Ways to soften the power delivery: - slow action throttle if not already fitted (has white plastic tube under the grip) - extra head gasket - retard ignition. This has been covered in previous threads on the Trialscentral Sherco forum, or google "sherco ignition timing guide" Enjoy the bike.

Well done, better safe than sorry!

Lovely bike. So lovely that given the nature of recent posts a well known contributor to this site will probably be on here in a minute to say you shouldn't advertise your home address in the photos...

Kill switch doesn't always do the job in this situation, as if fuel self ignites at extreme revs. Flicking the choke on has been known to work, otherwise whip off a glove and stuff it up the exhaust. Both of my twinshock bikes are set up with a decompressor, which is guaranteed to end the trauma swiftly and painlessly.

Surely its only a five when you actually have to get off the bike and push it out of the section. Or am I missing something here? Could be missing something, yes. The rules, perhaps?

Cleaning and repacking silencer likely to help noise and performance if you can find a way of opening up and resealing the silencer.

As I recall back in the day I cut off the last two inches of the silencer by sawing through the outer skin, then cut four or five slots in the side of this piece so that it could be opened out slightly and fitted as a cap over the end of the silencer. A jubilee clip around this closed up the slots so preventing leaks and securing everything in place. This created an easily removable end cap so cleaning and repacking could be done at will.

Not politics,but common sense really.A TYR is going to be a top weapon in the air cooled mono class which time rolling on will dictate as being the next big thing in "Classic trials". Proper Pre65 bikes are in serious decline,(However much I'd like it not to be...) the lightweight Bantams,Cubs and James etc are still going strong - but everything is about twinshocks.Air cooled monos are next,and the TYR was probably the best overall of the lot of them.(Certainly as a clubmans bike) So keep it as a mono and enjoy the A/C mono class on it. Sound advice. An AC mono is likely to gain value, one which has been hacked about to create a twinshock which is ineligible in that class in many trials would be a valueless clunker.

It would never be better than a Beamish Suzuki, which is at best a ho-hum prospect for twinshock trials.

Nice video. And it gives the rest of us hope that one day we, too, could rise to the ranks of Daredevil Bikers.

Definitely 315 Unless of course it's had about 15 owners and been hacked around and neglected for half its lifetime, and the Gas Gas is a cherished beauty which has been looked after. In other words, you can't make a definitive judgement on make alone. At this age, condition is everything.

Agreed. Trials has probably profited from being a low key sport, out of sight of the general public, in fact for me this has always added to its charm. Only this week a TC member posted to say how happy he was to ride his bike on any piece of private land he fancied without bothering to seek permission. There is a point where attracting more people to trials will increase this sort of dangerous and irresponsible behaviour, such that trials themselves will suffer.

Is the squeak there all the time or does it sometimes disappear? Does the frequency vary with speed of the bike? If so does it coincide with the chain doing a full rotation? If so that would be the easiest thing to eliminate. Although you've checked it by rotating the wheel slowly a dodgy link might show itself at higher speeds.

for me, dry = 6 psi 4, wet = 5.5 psi 3.5 good body position and throttle control is most critical in wet. rob Same for me, but for practising I've taken to raising the rear pressure by up to 2 psi to hone grip-finding skills (a technique once recommended by Mick Andrews as I recall).

Nice bike - as a side issue, are those old original Hydrobag rear units still damping? They seemed to give up the ghost long before this age!

My 1979 247c runs on 9 tooth front/40 tooth rear sprockets which gives good ability to cope with a general mix of sections and allows second gear to be used as a realistic option.

...and stifle development

Thanks for posting these results. For me a couple of results which stand out are Dave Thorpe, still riding to win and finishing well up the first class awards, and perhaps even more noteworthy one of the most "senior" competitors Colin Dommett claiming 7th out of 86 finishers in clubman pre 65.

Or wheel rims...

Helduns were made in the Birmingham area I think, in mid to late 60s. They did a scrambler and a road racer as well as a trials bike, all of 65cc I recall. I believe the trials version was called the Heldun Hammer, perhaps the only bike to be named after the trials rider's tool of choice.

Replacement liners are available from Diadora dealers

The big issue would be how people who wish to ride non-competitively would access land where they could do so legally and with all relevant permissions. In the UK trials operate under the auspices of clubs who often restrict their use of particular pieces of land to a specific number of times per year to maintain good relations with the landowners, and riding is strictly off-limits except for organised competitions. The days of "waste land" or "common land" where casual motor cycling can be legally undertaken are long gone. I am fortunate to belong to a club which owns its own (excellent) land which can be used by any full member at any time and there are "social groups" who go there to ride non-competitively in the way you describe but this facility is rare indeed these days.

How about disgruntlement with the non-stop rule/boredom with similarity of sections/lower order riders finding sections are bit beyond them?

Could be right about air cooled monos picking up in value over the next couple of years, and if this is a good one (hard to say without photos but the fact that it still has lights attached suggests it may be) it could be worth a punt at around £800 to 1000. Then again a TY 250 mono could be an easier bike to get on with, being the clubman's favourite of the time, and there are lots around.