dan williams

As I think of things on your Techno I’ll try to add to this. The stock pilot jet for this bike was a 30 but most people ran a 27.5 as it made response off idle a little crisper. If your bike is running fine you probably already have one though. Your bike looks to be in excellent condition with no apparent wear on the titanium nitride fork coatings. You might want to find some fork guards. They’re cheap insurance to prevent a nicked fork stanchion. For basic techniques there are other threads but stay centered. Steer with your feet. Keep your weight low and over the rear wheel when climbing... Have fun. It’s a silly sport but you can have stupid fun fur hours on a small pile of rocks. Welcome to trials. You’re now one of us.?

Hi Eric ? that looks like the Beta “Factory” clutch. The thing that bugs me about the factory clutch basket is it is directly coupled to the primary gear without the cush drive rubber thingys. I’ve seen lots of these shatter the teeth off the primary gear.

Right on the money!

Awesome! That’s a lot of success for one round of tweaks. I can’t claim the fuel piddle fix. That was the genius of one of my gurus Billy T.

To be more precise I prefer to SPEND hours HELPING PEOPLE ENJOY THEIR BIKES MORE. ?

Well the clutch fix is to deal with one set of issues the spacer deals with a different issue. Both clean up production tolerances or wear issues.

I put that together out of the parts bin but it's easy to make one. The normal bleeder is a vee bottomed screw that sits in an angled seat in the banjo bolt. Since it was threaded at the top of the bolt I figured I could just use a screw of the proper size with a copper sealing washer to seal on top of the bleeder and it should work. Yeah it spills brake fluid when you bleed it but I think that is going to happen no matter what. Plus it's titanium! Bling! A regular steel bleeder bolt won't have the higher part on top so it would probably fit better. It'll take some fettling to make it work but it's not difficult. Pretty sure it's effective since I almost went over the bars hitting the back brake over a log Tuesday. ? Of course you can just burp the bolt that's in it if already. Works just as well and is cheaper.

The ‘92 with the gold frame was hideous. Especially after the black and green beauty that was the ‘91.? The ‘96 was a lovely smooth bike. One of the reasons the Mikuni piddles fuel is the vent lines for the float bowl are so long they act like siphons once fuel get up in them. If you nip a small hole in the vent lines above the level of the float bowl they usually stop piddling.

Ask ten Beta owners what the worst maintenance task on a Beta is and eight of ten will say bleeding the rear brake. The other two don’t work on their own bikes. OK maybe that’s an exaggeration but it really is evil. My rear brake has been squeeky and weird since a get off last year that bent the disk. Replacing the disk helped but still not right so I went to replace the pads and the hex head on the pad retaining bolt stripped out. Ugh! Screw it. Replace the caliper though I know it meant the dreaded bleed. Hook up the lines, fill the reservoir and pump, pump, pump.... Too much air to make it work. Syringe back bleed to the master alternating push/pull monitoring level in the reservoir got rid of most of the air. Some resistance to the pedal and some pump- hold-bleed-close cycles got it closer. Now the party trick. Pump-hold-bleed-close cycles with the bleeder on top of the banjo on the master cylinder. Took about ten cycles to chase out the remaining air. Still not quite the pedal of doom so I eyeballed down at the disk while the pads engaged and the disk was moving. Disk brake systems are designed to be self aligning and they are on a car where the disk is strong enough to force the pistons into equalizing but the disk on a trials bike is so thin it will flex and then flex back once the brake is disengaged. This little bit of flex acts like a bent rotor only pushing one piston back and the caliper never sets up properly. The fix was to feel the direction of disk flex when applying the brake and apply gentle pressure to the opposite side of the disk to force the weak side piston to adjust out to where applying the brake doesn’t flex the rotor because it is centered between the pads. Much better. This is my custom bleeder setup. Yes it’s easier to just take the airbox out.

That works too?. If your working in your garage it is easier to just take it all apart and once you’ve done it you realize it actually pretty easy to pull the whole bike apart. But for parking lot, mid-event fixes like a blocked jet it really is pretty easy to pull the carb out one you figure out how. For me the big ah-ha moment was sliding the rear air boot back.

Worth pointing out two tools that are extremely useful and hardly thought of. Hemostats are those locking tweezer thingys that are used in surgery. I use them (depending on size) for holding components for soldering to chasing rubber boots onto carbs to retrieving small parts from inaccessible places. You don’t need them often but once you do you’ll be glad you have them. Places like Amazon or Harbor Freight sell cheap sets. Other surgical tools are also handy like small angled scissors. The other weird tools that have proven really useful are dental picks. Stainless steel picks bent at various angles with sharp points. I used one yesterday to clear dirt from around an air screw on a carb. Also useful for picking o-rings out of recessed grooves or cleaning silt out of calipers during rebuild.

Squirt some WD40 or similar lube on the inside of the rubber manifolds. The best way to get the carb off is to remove all the clamps and slide the rear air boot all the way back until it bottoms on the air box. It’s easy to pivot the carb out. It takes some force but not so much you’ll be worried. Same to reinstall. Twist carb into engine side manifold first and rotate into position. This will collapse the rear boot. Use a thin tool (I use my comically long curved hemostat but a screwdriver works in a pinch as long as you’re careful not to puncture the air boot or shave metal off the carb) to chase it around the intake bell and once it’s on slide the boot onto the carb until it seats. Reinstall the clamps. Lubing the rubber makes a huge difference just like changing a tire.

It’s a fairly simple idea. There is only a small amount of throw in the clutch mechanism and tolerances and wear can cause freeplay before engagement which just wastes some of that travel. Hydraulic clutch actuators should compensate to some degree but they seem to not quite get it done. Bultacos used to have a screw to adjust the position of the throwout bearing to compensate for this. Maybe time to see if it’s possible to implement on the EVO. I feel another custom part coming on!

The world guys used to stuff steel wool into the silencer for sound test. The Betas are a fairly high compression engine which is why the need for high octane fuel. Also why you get that pop when the exhaust port opens. Restricting flow in the exhaust will slow down the top end of the engine as well as make it quieter. You could try blocking some of the holes in the silencer core to achieve this. A piece of thin sheet metal should suffice. Alternately you could buy a low compression head to reduce the pop and the need for race gas. One thing to keep in mind though is despite how loud it seems standing behind the bike the sound of trials bikes doesn’t seem to carry. Honestly. Losing track of your friends in the woods is a common problem as if you can’t see them you usually can’t hear them. Only know where they are when they yell.

Anything really different with the 2020? Aside from the bold new graphics that is.?

Snug em. The springs will keep them from backing out.

Yes it comes up from the underside of the card throat oriented opposite the picture.

4T has all six of the 3mm thick plates. I haven’t got one to play with so I’ve got no idea how to smooth out the engagement. Swapping plates might work either with some of the thinner plates or the kevlar plates from Barnett but it’s pure speculation.

Yeah the more screwy the behavior usually the simpler the fix. Your intuition was correct all along.

Be careful with air pressure on the Keihin as there’s a gasket at the base of the float tower that is impossible to find a replacement for. One other thing that can happen is putting the needle jet in upside down. Sounds ridiculous but I’ve done it.? The tapered hole goes up.

Keihins are prone to needing an occasional cleaning. The exit hole for the pilot circuit is tiny as in microscopic. Yes it looks bigger if you eyeball it (the little hole in the bottom of the carb bore behind the slide) but it necks down significantly. Even a tiny bubble of water in that hole will make it bog coming off idle. Best to pull it apart and run some carb spray through the holes. Usually clears it up.

Fans, and electric motors in general, have a very high starting current. If jumping across the temp switch makes the fan run every time then I think you’ve identified a bad switch. If you have an ohm meter handy you could let the bike heat up and disconnect the switch and throw the ohm meter across the switch terminals. It wouldn’t take more than a few ohms of resistance to limit the starting current to the point the fan won’t start running but would keep running once started. I did take a Beta fan into the lab once to measure the running current and it was about 0.5 amp but if I limited the supply to anything under 10 amps the fan would not start. I think you’re up for a new switch.

Machine wash warm/warm. Pretreat with stain stick according to instructions on the stick. Let the stain stick sit for a bit before washing to do its thing. Do NOT dry in dryer. The heat will set the stains. Also the heat will shrink the spandex. Air dry.

All on hold due to corona virus. Will update when the world starts spinning again.

New England Trials Association has cancelled all events until further notice. Pretty much everyone is in agreement that it is unfortunate but prudent.