herman

Now that the carb switch was complete with good results, a shakedown ride revealed another problem: The drive chain is rubbing the cases enough to mar them. The drive chain appears to be the correct size. I wondered if a thrust washer was missing behind the sprocket, but a schematic found on this site doesn't show one. I tried to pull the counter shaft in and out to check for some obvious play, but found none. I can come up with a washer of some kind without too much trouble, but I don't know if there are other issues that need addressed. Thoughts?

Installed an OKO carb per a friends advice and she starts and runs great!

Just got of the phone with a friend that said he was using the OKO on his Fantic with great success. He said Mid Atlantic Trials can set one up w/ proper jetting for about 130 bucks. I have a buddy that told me he might have a couple of 28 Mikunis lying around. If so, and I can snag one, I'll use the jetting you suggested to get started. He echoed what you said about the Bing saying that he had trouble with them when new..... and 40 years later it hasn't improved! Thanks!

Thanks, Mike. I actually found an earlier thread detailing the Mikuni jetting and am thinking that's the way to go. I picked this bike up to use as both a rider and a loaner to some guys I know that are thinking about taking up trials. Plus I just like the Bultaco marque...... As far as originality goes I can always save the Bing and keep it with the original and unbelievably awful air filter / boot setup. I went with the one piece filter boot, which looks like a much better alternative.

My model 199 a with the standard Bing 28mm is having an overflow issue. Just about every bike I have bought has had this problem and each one was remedied with a new float needle jet...... except this one. I have adjusted the float until I'm blue in the face. I either have no flow or over flow. I must admit my average mechanical skills have eroded over time, but my next guess is a bad float. Anybody want to weigh in and help an old feller that just wants his Bul to quit leaking so he can enjoy it?

Tank has been relisted. Too bad it won't fit my bike as it's in my hometown..... Here's the listing: http://www.ebay.com/itm/Bultaco-Model-125-Sherpa-T-Gas-Tank-/161843460951?vxp=mtr

Thanks!

I just picked up a model 199 A. I have a chance to pick up a Campeon kit tank from a 125 Sherpa fairly cheap. Will the Campeon tank fot the 199 A? Always loved the looks of those kits.

I've just acquired a solid rl250 and have begun disassembly for painting. Other than the flywheel weight that many suggest, are there any other mods that would improve the performance of this bike? I read somewhere that cutting the steering head and tucking in the front end 3-4 degrees would help the turning capabilities. Thoughts? Thank, Herman

Just finished my project TL270 and I must say I am more than thrilled with the result.... I ended up using a 270 cc piston kit, a heavier xl250 flywheel, and a cut steering head (1.5 degrees). The shakedown ride went quite well - I've never enjoyed a trials bike more in my 35 years of riding. The bike was pure joy.... and then, and you knew this was coming, she signed off with a misfire. Back at the ranch I started the investigation. The bike kicked over with good compression, but had no spark on what I would call a plug that had a good tan color to the ceramic part, yet had black carbon ash on the edge of the threads. Plug was new before hand. The points looked a bit burnt as well, so I ordered a new set and a used coil / condensor to try in case it was needed. The old points got so hot that the fibre plastic type washer on the points body was melted. Indeed the bike ran hot... OK, so with the new points / new coil and even the old coil - no spark........ I used the old plug after giving it a good cleaning. Am i missing something else that may have failed due to excessive heat? Other info: When assembling the motor I powder coated the cylinder and head. The ignition plate was adjusted about a quarter inch counter clockwise. As the motor spins that direction, I assume this is retarding the ignition. If I can get spark I'll readjust this closer to normal. I figured the bike would run a little hotter during break in, but it appears I've gone more than a little hot. I've considered running a colder plug in additon to the ignition adjustment. My air seal on the intake is good, so no worries there. Any advice?

Been working on the house quite a bit (building a half bath and drywalling/finishing the family room) with little time to ride. Plans are to have the work done before Christmas, at least that's what I told the wife. By the way, After the burn ban was lifted Saturday, I rushed home and tirched a bunch of brush and construction debris. I laid that TY pipe and muffler in the fire and cooked it for about 3 hours. It got pretty hot and once it cooled about two large handfuls of carbon fell out of them including a couple of chunks the size of my thumb. Project TY should be ready to ride as soon as I can repaint and install the pipe. I'll let you know on the TY as I plan to lok at it maybe Tuesday night. Feet up, Doug!

Hi all I have a chance to pick up an 86 TY 350 in very good shape for 600 bucks. By habit I always look into replacement parts for bikes before buying and see that piston / rings are unavailable. I can't seem to locate anything that interchanges, either. Given the few times I get to ride the odds are against ever needing one, but if so, any options? Can I swap top ends and go with TY250 parts?

After a 5 hour drive to pick it up, a 1974 TY 250 has found a home in my garage next to my RL, TL250, and KT. The KT and TL are works in progress. The TY exceeded my expectations as it appears to be a low hour unit. The previous owner, who claimed little to no 2 stroke knowledge, said the bike had a knock when first started and wouldn't stay running. The knock turned out to be the typical Yamaha engine noise. The running issue was as if the bike was loaded up and would not clean out. I checked the carb, a stock TK, and found it to be clean. The air filter was stock and somewhat gummy, so I pitched it. Bike still ran poorly. A closer inspection revealed black drool seeping out of the base gasket. I pulled the top end and found the normal amount of carbon, a clean cylinder wall, and a shiny looking crank. After flushing some more black drool from the cases, I reassembled and tried again. Still blubbering. A friend happened to be there and noticed that there was no exhaust coming out the silencer. Yep, the muffler was plugged tight. With it removed the bike ran much better, but still a little erratic. I plan to go ahead and replace the points, seeing as how I've already given the bike the once over. As far as cleaning the silencer, what would you gents recommend I use? I don't own an oxy/acc torch. The finish of the pipe is outstanding and I'd like to avoid marring that. I figure I'll clean both while I'm at it. Any ideas are greatly appreciated. I'll post a pic once I get her back together. Thanks, Herman

I'll do that. Thank you for the replies. Herman

Yep, there was a hidden 4th nut under that plunger and once I removed it, things came apart nicely. Although I found rust on the breaker plate and camshaft end, the top end lookked pretty decent. Quite a bit of carbon on the piston crown and some ring wear. Looks like the partially stuck intake valve caused the lack of compression. Oh well. Gonna freshen her up with new piston/rings/valves anyway. Gonna need a camshaft, however. Question: does the XL version, same year, use the same camshaft?

Thanks for the advice. I' have a couple of days off starting tomorrow and I know exactly where to look for a hidden bolt. The microfische on bikebandit shows a nut under something called a sealing cap that is the same as the other head nuts. Under this cap is an O ring. I should have known......

Started disassembly on the basket TL 250 project and everything went fine until motor disassembly. I knew I might be in for trouble when I pulled the points cover and found a rusty ign. plate. After the end of the camshaft snapped off with the ignition advance unit I knew it for sure. Still, I kept going.... removed all fasteners for the top end (there sure are an odd assortment of them), and tried knowing it wouldn't go easy, removing the head and cylinder. Other than a smal amount of movement at the base of the cylinder, the thing won't budge. I tried the usual slight prying and tapping with a rubber mallet with no luck. I really don't want to inflict any more damage, so I'm wondering what you folks might recommend. I've heard submersing the motor in ATF might help. Heck, I'd whiz on a spark plug if I knew it would get the job done!

My pal Doug sez I better introduce myself.... I've been riding for nearly 35 years and have owned about every trials bike made... current project is a KT 250. I'll be leaning on you guys for a lot of advice, so be warned!

I have an extra swingarm as well as a new mig welder! I'll give it a try and see what kind of welder I am after many years... The long shocks are a good idea. I really appreciate the advice, too. Forgive me for pestering Doug. I met him last year and he really bailed me out by buying my Maico when I was strapped for cash during my house purchase. He's good people. I reckon I'll have to ride that wheey TL 125 this weekend... can't let the old boy ride his first meet alone, can I? At the least I can be his minder.

Introduction? Why Dougie old boy... you already know me. You bought my Maico last year! As far as Stoney goes, All I have is my son't anemic TL125, but I may drag it out and attend. I rode the event last year on my Sherpa and had to retire ealry with a DNF. I'd attended the meet annually and always enjoyed it, although it was pretty rugged on an old bike. last year, however, the trialsmaster set up a pretty tough course with limited lines and I really struggled. It just wasn't as fun as it used to be. I realize the event is for modern bikes, but it sure is harder for old bikes and novices. I've noticed an dwindling number of riders over the last few years, too. Not everyone is an advanced rider.....Just my 2 cents. Anyway, are you planning to ride both days?

Team Oolitic... you got it!

Greetings all! Ater months of waiting, my KT 250 project is about to get under way! I'm starting with 2 semi complete bikes that I'm certain will be enough for 1 rider. As the bike is going to be ridden, I'm planning on rattle can painting the tank (unless I get my powder coat setup done), as well as painting the frame to match the tank. I saw a great photo of one on this site that featured a lay down suspension setup for the rear. A buddy of mine can do this, so my question would be where to locate the upper mount and how much gusseting? I'm thinking about positioning the mount so that the stock length shock will be appx. a half an inch longer thinking tis will help the bike turn sharper. Suggestions Also, where can I get a flywheel weight for this bike? I had a weight on my RL and loved it... even have the plans to make one for the Suzook.. ANy other mods you chaps might suggest? Thanks, Herman