dan williams

It sounds like a caliper or disk issue. Take a close look at the alignment of the disk in the caliper. Does the disk run true? Got the disk guard spacer in the right place? Is there paint or dirt between the fork leg and the caliper?

Trials tires will find traction far superior to a knobby in every situation except deep mud or sand. Not even sure a standard knobby would fit the Beta’s swingarm anyway. The bike can be more comfortable with the accessory seat but you will still feel a little cramped as the footpeg position is further back than a standard woods bike. Shifter and rear brake are tucked in to prevent breaking on obstacles so they are a bit of a pain to get to sitting down. The short suspension and short wheelbase are great for tight trails but can be twitchy on faster trails. You may find trials gearing a bit odd as the first four gears are very close and fifth and sixth are spaced fairly far out. Top speed with stock gearing is very low and you can easily top out on a fire road. You can gear up fairly easily but a 200 may not pull a higher gear as well as a 300. Much depends on the type of trail riding you are doing. Tight technical stuff the Beta will easily eat up and make you feel like a hero. If you are looking to go all day at a usual trail speed for a typical enduro bike you’ll find the Beta’s cooling system, brakes and suspension are not really designed for that type of application. If you just want to tool along with the occasional run at something technically challenging the Beta might be perfect. If you buy one you’ll have fun but you may not have fun the way you think.

Look at the bright side, now the switch is safely out of the way. Of course the CDI is now there but that’s not important.?

What we really need are “Bold new graphics” telling us the difference between 1 and 2.

Yup we all take diggers!

Only things I can think of is a worn or damaged shift drum or a damaged shift fork. A damaged gear might do it but would probably make quite a bit of noise. Is it just those two gears? Is the shift from fourth to third OK?

Winner!

Same as mine. Was awesome to start with. Now I’m slightly spooked. It’ll be a few weeks before I get the rest of the parts to try the cam follower with the smaller bearing but I’ll post once I get it all together.

And possibly explosive?

Manufacturers saving pennies basically. Good designs implemented by bean counters is how most products go wrong. They work good enough to get out the door but are never fine tuned enough to be perfect. What's fascinating to me is the various reactions from owners some saying just get on with it and ride the thing to those like me who will have custom parts made and spend hours twiddling to make it perfect.

Any Mikuni VM series parts should fit.

Er, welcome to the forum?

The Mikuni is quite a good carb when tuned and you may be confusing some things here. The classical definition of flooding an engine comes from the days of carburetors in cars that had accelerator pumps. If the engine wasn't running and you pumped the throttle too many times the intake manifold was full of fuel often fouling plugs with gas. These carbs don't have accelerator pumps so that can't happen. The problems commonly ascribed to the Mikuni is a condition where fuel gets splashed up into the vent tubes for the float bowl and then continues to flow because the vent tubes are too long and end below the float bowl causing them to act like siphons. The vent tubes are the two hoses that come out of the sides of the carb. The other hose that comes out of the bottom of the carb is the overflow for the float bowl. If fuel is pouring out of the overflow your float valve is malfunctioning. This could be an assembly issue, floats rubbing on gasket, adjustment way off or a worn /damaged float valve. First off remove the carb and nip a small hole in both of the vent tubes about halfway up the carb body. This kills the siphon action and any fuel that gets splashed up into the tube will just flow out the tube or flow back into the float bowl. While you have the carb off open the float bowl and make sure the floats are not rubbing on the float bowl gasket. If the show and wear marks trim the gasket with an X-Acto or similar razor knife. Make sure there is no gas in the floats as they can spring leaks and hold the valve open. Check adjustment for float height and travel (that little tab that's bent at a 90 degree angle and hits the tower the float pivot pin goes in). The valve only needs to open a few mm. More than that and you won't get anymore fuel flow but the floats will slam around causing the mixture to be inconsistent over rough terrain. This tab is usually set to allow far too much float travel. Check the Viton tipped needle for debris or damage and same for the brass valve seat. Big advantage of the Mikuni is the replaceable valve assembly. The Keihin is just machined into the body. All the instructions for soldering tubes and drilling extra vent holes is overkill. Nipping the holes in the tubes works. As for starting issues that generation of Betas was infamous for the ignition trigger coil going bad. It's easy to think the problem is caused by the dribbly carb but it was often not the root cause. ...and I hate Del'Ortos

And on a slightly geekier note I think I realized why the cam profile looks familiar. It’s a sine wave wrapped around a curve. I think only Jon will appreciate that detail. The rest of you just think I got too much time on my hands.

Ooooo more experimental parts are in.

I think there’s still some hydraulic lock that makes the bike jump a bit when the clutch is cold and hasn’t been actuated for a while but it’s still a lot better than the drag across the parking lot you get from the glue. The four strokes seem to have less consistant results and that may be due to using six of the thicker fiber plates.

Lay it on it’s side. Remove shift lever. Take off the four allen head screws on the clutch cover. Remove clutch cover being careful not to damage o-ring. Undo six bolts holding clutch pack in. DO NOT PULL THE CLUTCH LEVER AFTER REMOVING THE BOLTS!!! Don’t touch it or you can pop the piston out of the slave cylinder and a simple job will become a real pain. Remove springs and washers. Remove pressure plate, bearing usually comes with it. Remove clutch plates. I find the best tools for this are dental picks. They allow you to reach under the plates and pull them out individually. At this point you can reinstall the o-ring and clutch cover if you don’t want to leave the bike open on its side. Don’t touch that lever though. I’m warning you!!! Now dress the plates removing glue and polishing the tabs per the clutch fix instructions. Reverse the process to reassemble the clutch pack. Once the plates are back in and the pressure plate and bolts/washers are back in you can pull the lever with the bike still on it’s side to see the pressure plate move. Put the cover and shifter back on and go ride. Piece of cake except for the mind numbing effort of cleaning the plates.

Grab the clutch lever and open the bleeder on the engine case. If fluid comes out and the lever compresses the master cylinder and hose are good and you have a mechanical problem in the clutch assembly/slave cylinder. This is usually a problem caused by incorrect assembly of the clutch and/or actuation mechanism. http://www.sherco.com/tl_files/core/pdf/spare_parts/WEB-Spare_parts_FACTORY_2016.pdf

This should be sufficient. Spacer clutch order 05-18-2015.pdf

That would be my guess. Of course without a schematic I could be wrong but it seems the only way the thing could work if you are correct about the other connectors.

I believe the yellow wire is the ac feed from the stator. I assume the ground lug is the other side of the ac feed so it needs to be bolted to the frame.

“I don’t get it Luigi, We never have enough of these cam follower arms!” Luigi, who assembles the kick stands, quietly snickers.

Anything look familiar?

So while I’m waiting for parts to experiment with I wanted to tighten the kick stand which is, as always, loose. So I take it off to have a look and.....

Looking at the press release for the RR125 lots of interesting stuff jumps out like integrated clutch MC in the side cover. Ability to add electric start to the engine. Different metodology for making the gears. Some of this could carry over to the trials bikes. It’ll be interesting to see if they want to compete with the Contact ES.