goudrons

There are a few areas old TY's suffer from. The first is from hamfistedness. The crank is a very tight fit into the main bearing, mag side and some owners have been known to wallop the end of the crank to get it out. This obviously isn't good for the crank, even if you leave the nut on the thread and you can actually bend it or knock the alignment out. If you haven't the tools to press it out, it's best to heat the case up a bit so the crank and bearing come out as one, then a puller to remove the bearing from the crank. Another areas worth checked, particularly after a rebore is the chamfer of the transfer ports. They need a good chamfer top and bottom otherwise the piston catches. I suffered and found this out myself a few years ago. I did a rebore and new piston and it rattled from the off, not your normal worn bore/piston rattle, but a loud metallic knocking rasp. When I pulled it apart I found chips of metal in the bottom of the crank and some impact marks on the piston edge. Checking the bore and it was clear the piston had been catching the edge of the transfer ports.

I've had water cooled Beta's since my 1991 Zero and they all at some point knocked and banged on regular 95 octane, some more than others. Before taking anything apart, try running it on 98 or 99.

Here you go, these might help https://www.betausa.com/content/trial-model-history-0 http://trialsport.com.au/beta/Parts/Zero 91.pdf

I'm pretty sure that's a 1991, I had one way back. They were either 240cc or 260cc. They weren't a bad bike back in the day, frame/tank was a bit unkind to your knackers if you got thrown forward and the water pump driveshaft wore/rusted up. Was a bugger to sort as there are lots seals and bearings for it and the cases need splitting to get at them all, as it picks up the drive from one side of the crankcases and goes right across the engine to the pump on the other. Another weak area was the swinging arm pivots, the voids where the bearings and bushes fit were quite thin and brittle and tended to snap across the top of the voids. As time wore on some of the other alloy parts got a bit brittle as well. The original rear rim was a flanged DID, I seem to think the same rim was fitted to the earlier Montesa 315r's. (later 315r's had similar flanged rim, but milled out in the gaps between the spokes, not sure one of those would lace up) Not sure if the Techno shared a CDi and coil with it, have you spoken with John Lampkin at Beta UK?

I use a Berlingo, the MPV version, I've used in it VX Combo's as well and it's not impossible, in fact it's easier when working with smaller vans. Push the bike in and slide the block under, if you've made it around 12" to 13" high, you don't need to lift it. I don't even get in there with the bike, I can do it all from the rear outside. I don't need to hold it up while I get the straps on, it's there sitting straight for me, I just reach in and attach the straps to the foot rests from the rear. It works for me and it may work for others which was the jist of this thread, it's very simple, can also be used as a support for working on the bike, it gives me a much more solid tie down and so cheap it's almost free.

I've done the same and never compressed my suspension, I guess we both can't be doing it correctly. Perhaps you might consider sharing how you do it? After all, the OP was looking for some suggestions.

If you had read my original post, you'd understand I do. I tighten it enough for it to go no where, without compressing the suspension and with as little force on the straps as possible. Using a block under the sump allows you to pull the bike down on to that rather than pull it down against the suspension, it won't bounce on the straps and as a bonus you can prop the bike up on it without having to hold it while you strap it down. Make the block just tall enough and you can also use it as a stand if you need to work on the bike in the field and the whole thing costs peanuts. I gather I may not be totally alone in my thinking as the concept of blocking the suspension is nothing new. "Fork Savers" have been available for motorcross bikes for years, but they only do half the job and aren't suitable for a trials bike due to the mudguard arrangement.

Your cheap 25mm racket strap is capable of putting around 800kg of force through it. I doubt the wire in the springs that are made to support around 70kg of bike and an average rider of say 90-100kg are designed to be held compressed under even half that load for any length of time without damage. It's designed to hold 165kg - 200 kg in it's natural uncompressed state, and not to be held compressed with 800kg or even 400kg on it. You wouldn't load an average car with 800kg in the boot, so yes it's a massive force to hold a bikes springs under.

I used a bit of 2 by 2 and made a wooden block that is just high enough to slip under the sump guard. It's about 12"x 12" x 12". Once slipped under there, I ratchet down from the foot pegs and the bike clamps down on the sump guard rather than the suspension. It's all very tight without having to put massive force back through the frame and suspension with the straps. Two straps are enough, but if you use four, one For and one Aft each side, the bike will go no where. I did the same trick with a trailer, Bike sits over a bar under the sump level with the trailer axle, the rear wheel swings free over the rear. It's really only half a trailer, as there's nothing at the back, it sits up right against the garage wall out of the way. Again, you get a much tighter hold without pulling too hard on the frame and suspension.

These sound like your problem, lack of fuel getting through. You need to pull the carb again. Strip and clean it, pay close attention the jets aren't blocked or any of the overflow/breather pipes. Next you need to set the float height for fuel in the float bowl. Due to the angle the carb is fitted, the Rev3 is very fussy to how the level is set. Too low and it'll starve, too high and it'll flood up and pee fuel everywhere, set it really high and it'll just pour straight through the carb and into the crank. You might find the setting on the forum somewhere and it'll be in the handbook which you should find on the net somewhere. The Mikuni carb isn't the best bit of kit and it can take some time setting it up, though this should be pretty easy and straight forward. When I ran Rev3's I binned the Mikuni for a Dellorto, the difference is quite apparent and they run far better, but are a lot fussier to set up.

The lower tube is the float bowl overflow. If the bowl over fills, it'll pour over a vertical tube within the bowl and out the pipe. It also works as a breather for the float bowl, stops a vacuum being created in the bowl as fuel is sucked out. The second one on the side is a breather/balancer, it evens out the air pressure inside the carb, again fuel pouring into the bowl and being sucked out again tends to create a vacuum if it's not open to air entering. Some carbs on the inlet stub or on the manifold might have a further pipe that would have attached to an autolube, a system of metering and pumping oil into the engine instead of premixing the fuel. It there was one and the pump has been removed it'll need blocking up. Over the years most of these overflow/breather pipes get broken off or lost, simple enough to replace with a bit of tubing, that'll stop the naked barbs blocking up with muck.

Talking of Mercedes Vito wheel angles, check out this http://www.penso.co.uk/case_studies/vehicle-build-of-mercedes-benz-vito-taxi/ You can almost rear end yourself!

They relate to the United Kingdom, 7 days a week, 12 months of the year!

Same here, Combat Camo on my Combat Camo. Only trouble is if I fall off in the bushes, no one will ever spot me! I use those ex army goretex bootliners as well, much better than Sealskinz and a third of the price. When it's really cold, try something that wicks away the sweat under the rest of your kit, like Alphaskin shirt and leggins. Stops all the sweat and condensation cooling off against your skin.

I've managed to remove a dropped wrist pin clip by swilling out the crankcase with the normal mix of petrol/2T and blowing it out with compressed air from a can with a straw, the stuff used to clean PC keyboards and the like. This canned air is really useful stuff and worth keeping in your tool box.