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  1. I have just re-read my old thread - https://www.trialscentral.com/forums/topic/70087-2001-250-smoother-running/page/2/#comments and it remains true to the results as time has gone on. Nigel
  2. Having now ridden a few trials since the alterations as outlined above, there is quite a bit less, but far smoother power. Previously when in 4th and riding flat out the front wheel would come up as the power kicked in. The power is now far more controlled, but there is most definitely less of it(think TY 250 mono). There is never a shortage of power in sections when 1st is usually the gear of choice as it is quite highly geared. For the odd long climb in third the reduction of power can be noticed, but better than standard when the rear wheel might start to spin up as the revs picked up. It overall makes life far easier for me, but a better rider might advance the ignition slightly if they could use extra power. Me, I can only wish for being good enough to use it!
  3. Assuming that fuel tap / carb filter / starter jet is not blocked.............Mine was difficult during the cold weather, so I tipped it right over to the the left for a few seconds to flood before kicking. That certainly helped. If you still struggle, try a #70 to replace the #60. They are cheap and will get more fuel through.
  4. The bike now has the 122 main jet fitted from what was on closer inspection a standard badly stamped 126 jet(which makes sense!) and the Boyeson 2 stage reed valves. These and the previous changes of 35 from 33 pilot and retarding the ignition to minus 2.5mm on the stator/case mark with the fuel screw set at exactly 3 turns out,(changes now giving indication of lean/rich within 1/2 a turn) have given an engine that is far happier with a smoother and initially higher tickover that transits without a lurch as the throttle is opened under load. The engine picks up with the mixture sounding far better, with none of the previous knocks and bangs as the revs rise. The fuel is BP ultimate mixed at 80:1 The only drawback I have found is the now audible sound of the piston slapping, previously masked by the incomplete combustion resonating in the exhaust! My experience suggests that the options should be done in this order until happy with the engine performance. The jetting first as it is the cheapest and the ethanol content has definitely changed since earlier bikes were made, next the reed valves(065) as they should not lose but perhaps gain power and cost more(incidentally I got mine from the USA at almost 1/2 the cost of buying them here). Lastly the ignition timing, even if it is free if you have a puller, as you might be setting it for some loss of power and the previous changes might make it as smooth as you require I will be riding it in a trial shortly and later in the year when I am more at tune with the bike will try the bike with the timing set back to standard to see if there is any more power to be had. If any other comments are required, they will be posted on here no fail. Given what I found I am amazed to think that the previous owner(s) rode it as delivered. The changes have really made a big difference, so if yours is standard, have a go, one stage at a time and you should get a far nicer bike to ride. I have not turned it into a new bike, but it is one that reacts smoothly to the throttle and gives me more much needed brain time to concentrate on my riding! Thank you for all that have helped with advice it was appreciated and I got where I wanted to in the end. Nigel
  5. In reference to the comments of Konrad(and I do appreciate him trying to clarify) I do of course refer to the mark on the periphery of the stator plate relative to the right hand edge of the crankcase casting mount. Virtually all advice(and there is much, if both incomplete and inconclusive, hence my wish to leave a trail for future owners) inc diagrams on here relates to timing positions in this area. I am not aware of severe problems because of ignition not being exactly as per the manufacturer (unlike say points fired Yamaha twins where holed pistons were a real risk) so we are looking at the best compromise of power vs controllability vs smooth running vs kick back vs starting and the possibility of an influence of other mods like jetting and reed valves. For quick and easy alterations, it would appear that this is sufficient, especially as I might well be trying different ign settings after the reed and main jet changes. For now, to be clear there seems to be a better overall compromise which I hope to improve on yet again with changes that I will report on shortly.
  6. Update - especially for anyone looking at this thread in the future. I have now altered the ignition timing from how I found it, which was + 1/2mm advanced(due to my less then fussy alignment of the stator during the rebuild!) to - 2 1/2 mm retarded giving a total change of -3mm from the my starting point. The result is indeed a smoother pick-up without a lurch and the engine is now more controllable at low revs and no need to clutch it during initial pick-up. There may be a little less power, but it appears to be not a lot less. The tick over is noticeably smoother without playing with the idle circuit too much as I will be making further changes, and the engine sounds to be generally happier and smoother. It still feels a little rich at the top of the rev range, so I will be fitting a 122(from the 143!!!) main jet and the boyesen reeds this week. There is still the odd kick back during starting, but less severe and a less firm kick still manages to get the engine started. I did use the trick of laying the bike over to raise the fuel level in the carb and it did indeed start more easily, but the day was a little warmer too. I use this last trick on my XR400 and it has always helped when starting from cold in the winter. Thank you for all the advice, it has been very useful in plotting a way forward and I will report back after the next changes.
  7. Thank you for your replies coming so soon. A little more info to clarify the situation. The silencer, sealed triangular type, had the side cut out, cleaned, repacked and rewelded. The current oil is Silkolene MX type, label dropped off, but certainly no cheapo scooter stuff at 80/1 The carb was cleaned during the rebuild when I went to the larger 35 idle jet from a 33 as suggested by Splat Shop(Our USA Guru Copemech suggests a 36, but perhaps different amounts of Ethanol in the USA) as fuel has altered since the bike was produced. I use BP ultimate and there is no pinging under load and the jetting in the middle seems very good indeed.. The bike ticks over fairly well, if sounding a little rich, if trying to lean out the mixture(screwing in the adjuster, as I am aware that it is a fuel regulating screw) There seems to be approx a 600 degree sweetish spot from centered around 2 turns out. It hunts a little around that area, but never running really badly until outside of that area. It picks up with slight hesitation/ 4 stroking - suggesting lean, but sounds a little wooly, which suggests rich! I hope you get my drift on that. Perhaps I am expecting too much, but having just ridden a friends GG200 pro where the jetting was such that it ran off the bottom so smoothly, almost like an electric motor, I have felt how good it can be. There could of course still be dirt in the carb somewhere, which I will clean out again when fitting the new main jet + reeds which I already have. There are jets available up to 180, some listed as Idle/Main, are they one and the same, albeit with differing holes? I cannot confirms 143 until stripping the carb, but remember double checking as it was so far away from standard (126) I hope I have now made it a little clearer. Thank you for all the help so far.
  8. I have just rebuilt a 2001 250 with new mains / seals / ring / repacked silencer and running pretty well considering its age, with lots of compression. There are a few queries about improvements that I hope to make. Any comments are most welcome. Firstly, it it has a 35 idle jet and is a little blubbery on tickover, it is not responding that much to the mixture screw until it is turned approx 300 degrees either way with no real sweet area and it at times seems both too lean and rich as the throttle is opened. It is sometimes hard to start from cold, as perhaps the idle jet is set too lean. This may be a reed issue which currently do not close 100%, as when it does pick up a few revs it flies!. I am going to fit Boyeson 2 stage reeds so I hope that will sort the tickover and transit as it once did for a TXT270. It can at times kick back whilst starting so am going to retard the ignition by 4mm at the stator, which should also help transit too. It is fitted with a 143 main jet! Now considering that Splat Shop recommend a 122 for the UK it seems far to large! The bike does rev quite high, but then seems to run rich at the very top. I am a little wary of dropping the main jet by that much as I think that if it runs fairly well, albeit not perfectly on a 143 jet, a 122 will be far too small. Were Shercos ever delivered with running in jets as some MX bikes were? It already has a slow throttle, so in which order would be best to make the changes? I do not want to have too many changes in to deal with in one go. Thank you for all that have helped with issues with this and other bikes before, feel free to do so again. Nigel
  9. Tried to send you a message but it won't send.  Is the TY still for sale? A friend of mine who isn't a TC member saw your ad and is interested. If it is can you let me have a contact number as there isn't one on the ad -  or you could email any pictures you have direct to him - Colin  email address     leese898@btinternet.com

    Thanks, Dave

  10. I have just put my newly rebuilt 250 into the frame and the gear change lever is solid in a |(do not which one) gear, the lever is solid! I am trying to sort it out without having to strip it all down again. Can anyone give me any tips on what to look for? It rebuilt it a while ago, and it all seem quite straightforward, but perhaps not!!!! The gears which were all kept together cannot go in incorrectly, the fork shafts again have one way only. Can the selector forks go in incorrectly? Mine appeared to go in just fine and from memory cannot go in incorrectly. The crank turns just fine. In my wisdom, I did not try to select gears until the engine was in the bike(bad move) and I now have the side cover and clutch off and and shortly to look at the mech in the clutch cavity. Does anyone have any input here as I really do knot know what I am looking for and do not want to strip further unless know what I am looking for. Thank you for anyone that can supply any however small advice. Nigel
  11. There was a at least one tl250/305 made. I saw it for sale on ebay in the USA about 2 years ago. It was green and nothing like the works bikes. It was new(ish)!!!! and went for about £3k! You will need new engine plates made, but it can be done. This might be the same bike. http://veh-markets.com/motorcycles/honda/312147-honda-tl250.html
  12. Thank you all again. NJB are now off my list, so too are Falcon due to repeated issues of leaks which my option - Rockshocks appear not to suffer from. Even if they do I will be able to service them myself and cheaply too. Unless I replace the one shock that has lost all it's oil with a second hand one, I will have to buy shocks before I can ride it and work out the best way forward. The problem now is the silencer, to go longer, it is going to foul the longer shocks. I have seen a few different attempts at a new silencer and wonder what people are using and what the resultant power/power delivery is like. The CT200 options is going to be expensive(£250+) and will require a new mounts and a different pipe constructed to match up with the exhaust pipe. What other options are there, none off the shelf that I am aware of. I wait to be shown a viable alternative. Nigel
  13. Thank you all for your help, but I am still undecided how to go forward. The additional shock length was to achieve two things. 1) to increase the ground clearence and 2) to quicken the steering. I do not want to change shocks again when I cut the frame and pull in the forks, which will raise the front slightly too. The longer shocks are a compromise, with downsides re chain torque effects and raised C of G. Honda were not stupid, but there again the world has moved on and perhaps the only way forward for a better bike with no drawbacks is to lenghten the shocks and pull in the front end with the footpegs lowered to alighn with an ali plate replacing the lower frame rails I am curious about NJB shocks as there some good feedback in my answers. Previously I have read only poor reports, which is a pity as the shocks are cheap and Norman is a nice guy
  14. I have just aquired a 76 TL250. It apprears to run pretty well, but needs some fettling for trials. I need to sort out shocks and was thinking of 16" Rockshocks, but have some new 420mm Ohlins off a Armstrong MT500 that might work. Standard shocks are 360mm long, but there is mention on here of 16" (406mm) being a length that works in getting the bike to stear. It's now in bits and I do not want waste time sorting shocks when it all goes together so.....My questions are: 1) Has anybody got any experience of these Ohlins shocks on a TL or TLR perhaps (which has 400mm shocks as standard) 2) Is 16"(406mm) the longest that I can go if I get Rockshocks for some sort of stability. 3) Will 420mm be too much for stability. 3) Spring rates - I am 17 stone so my extra weight might cancel out the lighter TL over the MT any views. 4) Any other advice is most welcome as for now I will be riding it as fairly standard, then if it all goes well go for a lighter silencer arrangement (anyone tried to fit an alloy/stainless TLR unit), cut down frame rear and and an alloy sump to give greater ground clearance. Thank you for taking the time to answer. Nigel
  15. knobbly

    2001 2.5 Issues

    Will a Ohlins shock from a 2012 fit my 2001?
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