swooshdave

Now to be fair (and I'm very sorry to have clicked on that link) no one ever said that it couldn't be done. There is plenty of evidence on this site alone of odd trials bikes. Heck, if Jay's endeavors aren't proof of that I don't know what is. I mean just recently there were pictures of a Guzzi trials bike and even a CZ trials bike. I'm pretty sure they didn't leave the factory that way. So, can it be done? Of course. Will it be easy or cheap? Not really. But if those two obstacles aren't a problem, go for it.

That would be the Mk1. Extremely simple to work on and despite a reputation of having to fiddle with it, not that bad. Couple things to look out for: 1. Loose or stuck slide. Permanent fix is to get the carb rebored and a sleeved slide. There are a couple (or were) places in the US to get this done. A new carb will not be as good as a sleeved one. Also over-tightening the carb to the manifold will distort the carb and cause the slide to stick (this would be undesirable). 2. Clogged pilot jet. If I leave gas in the carb for too long and the bike is difficult to start I pull the carb off and clear the pilot jet. Usually solves the problem.

I thought it was insane. Now remember, I have never nor will I ride a new bike so all I have to compare it to is other vintage ones. But the steering was quicker (I'm coming from the M49 which takes days to turn, then to the M92, which I'm still getting use to), it's way higher off the ground and with the engine mods this one had, there was no shortage of power. I think the suspension on my bike is a little better. The owner said he's not happy his setup. But the bike never gets ridden so it hasn't been addressed. Also nice was the one finger clutch (!). Apparently he had a 250 clutch and the rear brake arm mod. The bike was ridden well into the 80s in the Expert class which says a lot for the rider and bike. If I ever get a chance to buy the bike I will. There was an identical one that sold here several months ago. Apparently several of the bikes were bought new at the same time. So there a couple in the area. If you could make it as light as some of the pre-65s they are making now it would be a perfect bike. I need to check to see how much titanium fasteners are... I may break down and get a Mukuni one of these days, but only as a last resort.

I wouldn't suggest Kreem to my worse enemy.

Might help if you updated your profile with your location. Makes it easy to determine if it's going to be easier to ship something to you or to point you to a proper vendor.

After multiple failures with POR-15 (in it's defense it's not made for fiberglass specifically) and the only tank that is holding up has Caswells in it, I concur with your findings. I'm currently draining the tank(s) after each use (if they are going to sit for more than a couple days).

I tried a Sammy Miller-framed Sherpa T M92 this weekend. It had a Pursang top end and had "plenty" of power. I don't know the porting specs for that bike but Jay probably does. I think the Sherpa T lower end (with flywheel, et al) and the Pursang top end worked well. It had more power than you would need in a typical AHRMA event, which are typically very low speed and moderate climbs that a stock bike can easily handle. But it would probably be ideal for ITSA and other Twinshock events.

Both MAVT and ITSA are still regionalized. AHRMA is national. And AHRMA likes to think they are still vintage, only from a certain period. The challenge with twinshock is that is appears to be catered to the newer twinshocks, thus leaving the older bikes out. AHRMA can be a good venue for the older bikes. My brother ran in the last MAVT event. Sounded like it was a tad warm.

I think the answer is there is no Twin Shock class... yet. The good news is that until then you can pick up the later twin shocks for ridiculously low prices. Until then the cutoff is 1979... which roughly corresponds with the last decent trials bike, the Bultaco. From what I understand on the East Coast the ITSA is actually more popular for trials than AHRMA. This is probably due to a heavy influence from B&J Racing. In the Western US, there are a number of decent AHRMA events, including two and even three day marathons. The drawback being the considerable distances that have to be traversed. For example for us to travel to Donner and back it was 1250 miles. With diesel costs where they are it's not cheap to get around.

I had a very similar problem. It was actually the gasket between the engine cases that was leaking gearbox oil into the crankcase. The exhaust definitely has a different smell when that happens. The good news is that the engines are relatively easy to work on. With a minimal number of tools you can split the cases yourself, if so inclined. Get the gearbox oil leak addressed and then you can see about get it running correctly. Can you post the model number of your bike? That will let you know the approximate year. You're English is just fine, much better than most.

I believe it's the "infamous" swooshdave...

Sounds reasonable to save a Norton...

And do you have access to a hydraulic press? If you ever wanted one, now is a good time as you have an excuse... If the piston is stuck it doesn't sound like you'll have it ready the Vintage Event down here in Oregon City nor Chehalis...

I prefer something like Liquid Wrench to WD-40. And heat. Where in the cylinder is the piston? Top? Bottom? I believe one way to get it loose is a hydraulic press. The most drastic thing I've heard of was one guy cutting the connecting rod. I've always had more patience than that.

By stuck, we assume piston + bore?

Hosted by one Kary Krahel with assistance from Mr. Jay Lael. Now I never really got a definition of "vintage" but I assume it's going to be basically a Twinshock event. I'm not sure if Jay is going to bring the Sherdaka out or not. Maybe just to demo it. It will be interesting to see what kind of bikes get dragged out from the corners of the garages. COTA Forums link with details

How soon before Brenda has pictures up from Donner?

Again.. don't mess with Texans.

Yeah, but with Firefox you probably won't loose a finger...

I could have replaced the coupler at home, but I figured that if I ran into trouble I'd just swap it out there. It didn't take too long. Air quality was better in the mornings, by the afternoon it was not so good. Not as bad as LA but still hazy. Can't make it to Donner, but you can to Mid-Ohio? I see how you are...

Jay, Matt would have let you ride the Sherdaka at Donner. The 1 line was a little less dangerous than what you saw at Lolo. There were both single shock and twin shock classes, in addition to all the vintage ones.

That is outstanding. Is there a great weight penalty with the engine? Were you able to get the gearing adequate?

Since I'm the only one reading this stuff I might as well write something interesting... Day One Day Two and: (scroll to the bottom of the page) AHRMA NW Site

We are assuming everything is clean. Have all the wear-prone parts been replaced? Have all the jets been replaced? Is the slide tight in the body? Fixing the existing carb should be less expensive than replacing it. But many people swear that a Mukuni or the like is much better. They are too complicated for me. But I'm just a simple lad.

Well, we made it here. More mosquitoes than people so far. Don't start riding until tomorrow.