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Glad I could help ....These old bike have little quirks that you have to work around or get use to , but that is all part of the vintage thing imo. I enjoy experimenting to get things working better especially if the bike responds to my efforts. The 72 247 ( that I no longer have) had to be held in to gear with the shift lever then release the clutch to have it stay in gear. Not a big deal in trials but kind of pesky for trail riding when you are doing allot of shifting. It never jumped out of gear however. good luck

My 74 is better than it use to be with the Maxima. I was using regular 90wt gear oil and had allot of problems with it jumping out of the higher gears while riding between sections and a few false neutrals in the lower gears. I switched to atf in both boxes a couple years ago and it worked better in my application. I just like the idea of having a heavier oil in the gear box however and the Maxima seems to be fine and I didn't notice any gear jumping. TO put this in perspective this bike has lots of hours on it so I am sure it has allot of wear on the drive train. I am kind of in the preservation mode with it but still competing with it at vintage trial events and doing quite a bit of practice on it. This bike never has shifted as well or as positively as most other bikes, and you kind of have to get use to putting up with it's little quirks, but it is a great vintage trials bike and I always get lots of compliments at events.

No I can't find a GL-4 classification on the bottle but it is working fine in my bike with lots of miles /hours on it.

I just switched over to Maxima MTL 80w gear oil in my 74 Cota gear box and use atf in the clutch/primary. The label on the Maxima doesn't say anything specific as far as classification but I trust it to work well. I just did a trial with it and it worked well. It also says it is compatible with wet clutches so I may just go with the Maxima instead of atf in the clutch/primary.... Sam

I believe there should be a circlip that holds the cap in place but it doesn't appear to be there. if you loosen the triple clamp bolt and push down on the cap from above you may be able to get it to loosen enough to see what is holding it all together.

Depends on the brand of sealer used as to weather you can see it in the tank. Some have a white or silver look and some are clear. I used Caswell epoxy sealer in my 74 247 and it is clear so it is hard to tell. The biggest thing on having success using a sealer is good preparation. Nice bike!

Check out Matrix Motor Sports web site and check out the clutch issue with these bikes. He has allot of info on the clutch for the RL250 and what sounds like a good fix along with other ideas on the RL250. Sam

Always good to hear progress! Sam

Is it a flange mount or spigot mount Amal? If it is flange mount the nuts might be torqued too tight warping the carb body causing the slide to stick. Sam

Interesting to know Larry and thanks for the info. Nice to have a side by side comparison. I have a little longer than stock shocks on my model 49 and I think it helps the turning a bit. Imo I think the front sticks better than my Cota 247 especially in off camber turns... Thanks for the input.. Sam

Interesting to know Larry and thanks for the info. Nice to have a side by side comparison. I have a little longer than stock shocks on my model 49 and I think it helps the turning a bit. Imo I think the front sticks better than my Cota 247. Thanks for the input.. Sam

Thanks guys... all good info and kind of what I figured but I never really looked in to it that far. Has anyone here ridden the Hi-boy framed bike and a stock factory bike side by side to be able to make a comparison? Just curious about the handling differences... Sam

I have a 71 model 49 and it has been restored at some point. Is there a difference between a model 49 and a Sammy Miller replica or is it just the sticker on the side cover? Or were all the early model 49s SM replicas? I see Sherpa Ts for sale claiming to be SM replicas and asking allot of money for them but how would a person be able to tell? Any specific frame or engine #s? Thanks Sam

OK I misunderstood .... GTX is good oil as that is what I run in all my vehicles. I am running Valvoline 80wt gear oil in my gear box as that is what I have available at the local parts store and have been thinking of going to something else. Maybe a motorcycle specific gera oil would be better. Thanks Sam

So are you using 80w/90 in the clutch box or gear box or both? I have a similar problem with my 74 cota drifting between gears between 3rd and 4th but I am already running 80wt in the gear box. I am running atf in the clutch box but I can't see how that would affect the tranny?? Thanks Sam

About the only other thing to check if you have eliminated all the possibilities of air leaks is you might want to go a bit larger on the pilot jet. Or It could be partially plugged or or it's circuit could be. When you say hard starting does it seem to load up or flood or does is seem to be needing more fuel? I always shut off my fuel tap when the bike is sitting or it will load the engine with raw fuel.

Sorry ... I just meant the crankshaft seals and if you have replaced them then it must be ok. Sam

Hard to know for sure but it could be your crankshaft seals are shot and leaking air. If the clutch side leaks then it will suck primary oil into the bottom and smoke quite a bit. If it is the mag side it will suck air giving you a lean condition. If you have been through the carb and all is sealed ok there then I would suspect the bottom seals. It should just sit there and idle when hot and not gain any rpm. Sam

Glad you found one! So how DOES your GF feel about engines on the kitchen table ??? That is the real question! Sam

I basically used an old chain saw chain and ran it back and forth to break loose all the carbon for the mid pipe. I used a OXY ACC torch to heat the insides of the after muffler/ spark arrestor until the carbon was hot enough to flake off with a screwdriver. There was alot of carbon build up in both. I didn't have the guts to take a torch to the mid pipe because I was afraid if I ruined it I wouldn't be able to find another. The torch method works well but makes alot of smoke... I did all this on my 72 which has a smaller stinger/exit pipe than the 74 has. I can't believe how much better the bike runs... Sam

Before you change the carb make sure the exhaust is not plugged. They can get plugged with carbon over time and it can mess up the power. My 72 was almost completely closed off but still flowing and it made a huge differance when I cleaned out the muffler and mid pipe. It probably still won't be like your Sherco but may run cleaner. Also it may be time for a top end if it seems that weak. Both my 247s are good and strong off the bottom. Sam

Mine is geard down from stock with a 10 cs sprocket and a 56 rear. For me stock is too tall for competition. Just personal preferance but I installed a Domino slow throttle on my bike. I also put new Amal levers which work much better than what came on the bike. The only other thing I did was put a FMF universal spark arrestor on the exhaust for the spark arrestor feature. Gets pretty dry around here.... I am still running the stock shocks. Sam

I have a pair of NJB trials shocks on my 72 247 Cota and they work well. Mine are a little longer than stock so it has quickened up the steering a bit but not a problem. They are not rebuildable as far as I know and are mounted inverted. I got them from Matt at Speed & Sport and he helped me decide on the spring rate. Price wise they were competetive with others and less money that the Betors. I have ridden a couple events with them and no problems. Sam

Alot of variables here but I might think it could be a set-up issue. I have both a 72 247 and a 74 and they both stick well. The 74 has new Dunlops front and rear and I like them with about 4.5lbs in the front and about 5.5 or 6lbs in the rear. The 72 has a little longer shocks than stock and it handles a bit quicker but the front sticks better than the 74. The 72 has some older IRCs that are cracked but they still work ok for me. Let us know what you discover... Sam

I too have a 72 247 and have had issues finding a silencer that will fit the small stinger. I finally took a muffler that had the correct size inlet that was a Montesa muffler originally, and refabricated it to work on the 72. it looks good and is alot quieter than what the po had on the bike which was a small Krizman. I have also considered changing the mid chamber or muffler to something with a larger outlet but that starts getting expensive. Super Trapp sells the old style steel bodied muffler/spark arrestor that is the closest to the correct size I have found for this application , but I thought there might be some clearance issues with the back tire. It is not an easy fix to just find something to bolt on if the stock muffler is missing. Good luck and let us know what you come up with... Sam