calsop49 Posted September 18, 2011 Report Share Posted September 18, 2011 My Friend has just bought a Goddon Majesty TY250, it had been stood for several years, we have cleaned carb & tank out & put in fresh petrol, started up no problem, ticks over all good. However took it out on his practice track it seemed to pull Ok but power is very flat, not as good as his Ty175. Starts, runs, does not miss, just seems to lack any Oomph. Any Ideas ?? Quote Link to comment Share on other sites More sharing options...
petwar Posted September 18, 2011 Report Share Posted September 18, 2011 could be a number of things, blocked exhaust, gummed up rings, blocked airfilter? Quote Link to comment Share on other sites More sharing options...
old trials fanatic Posted September 18, 2011 Report Share Posted September 18, 2011 Timing ? Quote Link to comment Share on other sites More sharing options...
woody Posted September 18, 2011 Report Share Posted September 18, 2011 (edited) Sounds about normal... Difficult to tell from just a description to be fair, obviously it should have more power than the TY175 but as a rule, the TY250 is as flat as a pancake and usually a 1st gear only bike. If you're halfway up a climb in 2nd gear and have to shut off, the chances are it won't pick up again and it's game over. I had a Godden 250, the engine was sound and had just been rebored. It was 1st gear only. I hated it. And it was so much heavier than the Yam frame which was a nicer bike in my opinion, but that's digressing. Assuming it is mechanically sound and the timing etc is fine, check the ignition flywheel. If it has the weight fitted (steel band held on by 4 allen bolts) take it off. It kills the power on the 250. With the weight removed it will pick up quicker. In standasrd form they aren't the torquiest of motors, there are things that can be done, porting, head work, reeds etc. but standard, they are a lazy motor. I had a ride on a Tony Scarlett works bike once - what a difference... although that may have been one of the special 6 speed motors, can't remember now. Edited September 18, 2011 by Woody Quote Link to comment Share on other sites More sharing options...
mattylad Posted September 19, 2011 Report Share Posted September 19, 2011 TY250 can be made to work very well but requires some effort. Reducing flywheel weight means engine picks up quicker. Much more modern response. Air filter and inlet to carb very restrictive. I use a Montesa 315 filter with the original mounting at bottom of airbox removed. Squish normally very wide, remove head gasket is a good start. Also exhaust can become clogged with carbon, a good roasting on the BBQ helps. Quote Link to comment Share on other sites More sharing options...
jockster Posted September 19, 2011 Report Share Posted September 19, 2011 hi, my ty250 went flat, crank seals were to blame Quote Link to comment Share on other sites More sharing options...
jon v8 Posted September 19, 2011 Report Share Posted September 19, 2011 Sorry, I have to disagree,there is nothing wrong with a bog standard TY250 motor,nor do they need any trick mods doing.If its worn out,its worn out and needs a rebuild.I rebuilt mine back in 06 very carefully and it has done alot of work since then,including the Dartmoor 5 times - and it still runs as well as it did back then.I took the flywheel weight off for a while and thought it was an improvement - it wasnt,with it back on I'm riding it better than ever. Its not going to compare with a modern Gasser or Beta for instant zap,but saying it will only work in first gear is total rubbish,second and ocassionally third for a long muddy climb if it calls for it with no problems. Loads of people have ridden mine and no one has ever come back and said it was gutless - only how smooth and well it pulls.There is nothing special at all about it and the Quote Link to comment Share on other sites More sharing options...
calsop49 Posted September 20, 2011 Author Report Share Posted September 20, 2011 Thanks for everyones input, will start to look into it at our drinking Tinkering club, will let you know how we get on! Quote Link to comment Share on other sites More sharing options...
ducman Posted September 21, 2011 Report Share Posted September 21, 2011 Sorry, I have to disagree,there is nothing wrong with a bog standard TY250 motor,nor do they need any trick mods doing.If its worn out,its worn out and needs a rebuild.I rebuilt mine back in 06 very carefully and it has done alot of work since then,including the Dartmoor 5 times - and it still runs as well as it did back then.I took the flywheel weight off for a while and thought it was an improvement - it wasnt,with it back on I'm riding it better than ever. Its not going to compare with a modern Gasser or Beta for instant zap,but saying it will only work in first gear is total rubbish,second and ocassionally third for a long muddy climb if it calls for it with no problems. Loads of people have ridden mine and no one has ever come back and said it was gutless - only how smooth and well it pulls.There is nothing special at all about it and the Quote Link to comment Share on other sites More sharing options...
guy53 Posted September 25, 2011 Report Share Posted September 25, 2011 I have a 434 that I ride for fun at different comp that was refresh last year, at first it was Ok. I '' geared '' it 12 / 55 ( 428 chain )and was fun to ride but it went slowly very flat on me, to a point that it was unpleasant to ride. It did not slall on me but would not pick up. I cleaned the silencer ( help to a point I know I need to do a complete job on the exhaust ) put on a .020 in head gasket gain another bit and finaly change the original carb for a VM 26mm Mikuni ( ordinary round slide ). Now that made a big difference, so much so that I put the 13t front sprocket back on after an hour of riding. I think there's a lot of small thing that can make a big difference in performance. Quote Link to comment Share on other sites More sharing options...
calsop49 Posted November 8, 2011 Author Report Share Posted November 8, 2011 We have found the biggest improvement after replacing the condenser, still a bit flat but big improvement. Thanks. Quote Link to comment Share on other sites More sharing options...
pitley Posted November 9, 2011 Report Share Posted November 9, 2011 Bin the flywheel weight, worked a treat on mine Quote Link to comment Share on other sites More sharing options...
trialskat Posted June 9, 2012 Report Share Posted June 9, 2012 Surely there is a shop with knowledgable techs in England. Over here in the U.S. it's Bob Ginder in Tennessee. http://bjracing.com/ I rode a stone stock '74 to a AHRMA National Championship (Novice) in 2003 and during that time I had the opportunity to ride Bob's personal bike. This machine was like cheating. The power and deliverywere silky smooth and cleaner response across the band. It has head and port work,electronic ignition, exhasut etc. Bob knows his stuff and "someday" I'll send the head and barrel for the mods. Quote Link to comment Share on other sites More sharing options...
jon v8 Posted June 9, 2012 Report Share Posted June 9, 2012 Surely there is a shop with knowledgable techs in England. Over here in the U.S. it's Bob Ginder in Tennessee. http://bjracing.com/ I rode a stone stock '74 to a AHRMA National Championship (Novice) in 2003 and during that time I had the opportunity to ride Bob's personal bike. This machine was like cheating. The power and deliverywere silky smooth and cleaner response across the band. It has head and port work,electronic ignition, exhasut etc. Bob knows his stuff and "someday" I'll send the head and barrel for the mods. Well,it is a bit of a problem here in the UK,being a basic third world country we do struggle badly keeping our bikes going..... Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.