dan williams

Not unheard of but somewhat less common now with watercooled bikes as they can run more ignition advance than the old aircooled bikes. From a piston port two-stroke engine perspective running forwards and backwards look exactly the same for "valve" timing. The only difference is the ignition timing as the spark is supposed to occur before the piston reaches top dead center. If it starts easily backwards you may have shifted your timing significantly in the crash. First order of business is to pull off the flywheel and see if you sheared off the woodruff key that locks the flywheel in the correct position. If the engine sees a big hit, particularly at full blat it's not uncommon for these to shear allowing the flywheel to move on the shaft. If you've never pulled a flywheel you will need a flywheel puller and a flywheel holder. The flywheel holder is easy to make with a couple of pieces of steel flat stock. The flywheel puller you have to buy or borrow. If you have a buddy who works on Betas or Shercos they use the same flywheel thread. There are a lot of other "methods" to hold the flywheel. None is as safe for the crank as this. Works like a charm and allows you to re-torque the flywheel nut to ~100ft/lbs with no drama. IMPORTANT NOTE: Make sure the screws that go into the flywheel aren't too long or you will destroy the ignition coils. While you have the flywheel off do a quick visual of the coils and wiring. The backing plate for the coils is usually near the center of the slots. If yours is all the way to one side then someone may have moved it to retard the ignition for slower throttle response or advanced it for quicker response.

On some of the Mikunis the float bowl gasket impinges on the floats and causes them to stick. Easy to trim with an X-acto knife.

Use propylene glycol based premixed coolant like Engine Ice or Silcolene Pro-Cool and there is no problem. Tap water is the devil's coolant! I'm still curious where the magnesium that is being leetched away from the cases is being deposited.

DANGER WILL ROBINSON!!! I'm thinking again! Rather than go for weaker coil springs what are the thoughts on wave springs? Preload (lever pull) could be tuned with spacers. They should fit in the current hardware. What do you think Chewy?

Well finally managed to get out on the 2013 for a short putt. Probably wasn't the smartest thing to do while fighting the flu but it was 62F. A temp I'm not likely to see for some months and I had to try it out. I did the tab polish on the fiber plates but the clutch action is still a bit abrupt. Much as described by Chewy. I also suspect they didn't change the spring height/rate with the thicker pack making clutch pull very heavy. I'm tempted to process two more of the skinny plates and replace the thick fibers to see if Beta made a change that was not necessary. On a side note one of my friends put these in his 2010 Evo and likes them.

Smart to walk away. Have patience and a good one will make an appearance. Look for a bike owned by a senior class rider. They tend not to get beaten and the riders have the resources to properly fix them.

Welcome and good luck with the '05. It's a good solid bike. I just sold mine but it was a trouper.

OK the 2013 clutch plates look really good. Adhesive properly applied and the tabs are even if not smooth. I'll polish the tabs but I think that's about all I need to do. As for Axelsuv's Fantic, the 307 that my friend had was what started me on the Beta clutch exploration. The Fantics had the best clutch action I had ever ridden and I was determined to figure out why the Beta with a theoretically identical clutch was so bad.

Well well well, I took the plates out of the new bike and I'm pleasantly surprised. The adhesive on the friction plates is thin and even without glorping up between the pads and it is applied in a tight ring rather than splashed all over the plates. The tabs don't have adhesive on them nor do they have big ridges or high spots. The springs are even mounted with step washers though they were flipped on my bike to increase spring pressure. I think a quick polish with the Dremel and I'm done. Too right Beta!

Check for a split manifold between the carb and reed block.

Hopefully that's it. A seal kit is basically the plunger piston with a seal (the seal is already on the piston) and a spring. Remove the circlip, make sure the bore is clean and carefully slip the new piston in being careful not to damage the seal. Replace the circlip and the mechanical is out of the way. Usually the bleeding of the system isn't too bad since it's at the top.

I don't know but a letter from the former Canadian champion telling of his fond memories of riding a US national event at that location might be quite good, Eh Steve?

Alrighty that's pretty much backwards from what you'd expect but... If air is trapped in the hydraulics the clutch will be mushy from the start. If the lever isn't allowing the master cylinder to return all the way past the resevior bleed hole the clutch will slip more as the fluid heats up and pressurizes they system. If there is a leaky seal or hose the clutch will act as you describe when the clutch lever is held in as fluid pressure bleeds off the clutch actuation point will move and it will drag after being held in for a while. Since you saw no change with a disassembly of the plates I'm inclined to think the actuation mechanism is leaking. The critical question is does the clutch actuation point change while you're holding in the lever? Here's what I'm thinking, If the hydraulics are losing pressure it should happen while the lever is pulled in. The system should go back to a fully filled zero pressure state once the lever is returned back to the fully out position. Critical question is are you loosing fluid in the system? Maybe from a bad slave cylinder seal. Usually when the master cylnder seal goes at the handlebar you can see the leak. Also does the lever return all the way? I've seen master cylinders with bad return springs where the lever was set properly but the master cylinder never returned past the resevior bleed hole. The master cylinder piston should come all the way out to seat against the circlip.

Doesn't matter what bike I get from now on I'll be pulling the clutch to make sure the finish work is done on it. After 6 years of flawless clutch on my last two Betas there's simply no reason not to, short of lazyness.

OK I have to ask for a better description.What do you mean "I lose my clutch"? Does it not actuate? Does the lever go all the way to the bar with no resistance? You have to be more specific. Can you lay the bike over, pull the side cover off and pull the lever to see if the pressure plate is moving? Help us help you.

Heh heh "fan boys". I don't technically "have" the bike yet, couple more payments. I have not condemned the clutch. I will take it apart to see if the tabs are polished at a minimum. One of the characteristics of the poorly finished clutches of the past was inconsistancy from one bike to the next. Your clutch may be excellent from the factory. The next bike over, maybe not.

Yup, incentive to get my fat ass to the gym which will have more effect than the new bike.

Looks like I have another clutch to work on.

I gotta stop reading these forums. After reading about what a pain the Beta rear bearings are to replace I figured I needed to just get it done. Took about an hour. I feel like Robin in "The Holy Grail" "You git! I soiled my armor!"

There is a hole in the cylinder that the plunger must return past. The brakes are an open system. When they are off the plunger in the master cylinder is supposed to come all the way back into a rest position that opens the hole so there is a complete path from the caliper up to the reservoir. That way any expansion of the fluid caused by heating can’t build up pressure in the system and the next application of the brake starts from the same zero pressure point regardless of fluid temperature. Three things usually bung this up. The first is adjusting the lever so it partially pushes the plunger in part of the way as a starting position. This is common with riders who want their brakes to engage further from the bars. The problem is the plunger never uncovers the hole into the reservoir and as the fluid heats up from normal braking and expands the only place it can go is the caliper which forces the pads to drag on the rotor generating more heat and more drag eventually locking up the brake system. The other thing I have seen is the plunger return spring can be damaged by a fall that slams the brake lever on. This deforms the spring so even with the proper lever adjustment the plunger never returns to the proper rest position opening up the hole to the master cylinder. The third is debris blocking the reservoir hole. So yeah start with the easiest thing first and make sure the lever adjustment allows the plunger to come all the way back in the master cylinder to be stopped by the circlip that keeps it in the bore.

The Rev3 is a fairly high compression engine and really likes racing gas. The pinging is a sign of too low an octane. You may want to lower your compression with an extra cylinder base gasket if you can't get better fuel. I run VP C-12 at 108 octane in both my bikes one with Keihin and the other with a Mikuni and neither of them ping but they will ping if pushed using pump fuel, even with Sunoco 93. Well some batches anyway. I'm never sure of what comes out of the pump to be honest.

You don't say whether you have bumped up the idle which is a common way to deal with a misbehaving pilot circuit. This sort of bypasses the idle circuit, or maybe overrides it would be more accurate. One of the characteristics of the Keihin is the very small exit hole for the pilot circuit behind the slide. I have had the hole blocked by a bubble of water after riding in wet conditions and the only way to clear it was with a disassemble of the carb and a blast of compressed air. My suggestion would be to drop the carb and do a disassemble and clean. With compressed air and paying attention to blowing through the air passages in the carb body. I think that will fix your problem.

Only way to know is disassemble and have a look. You have to do it anyway.

Spot on, tire pressure is the most common newby mistake.

Hmmm I had a set go out on my '05. Paid a friend who's just become a dealer to fix them. Partly because I didn't have the space and partly because he needed the experiance. They didn't make any kind of swishy noise. They sounded like a rock crusher. Rather impressive actually. I'll have to keep an ear on my '08.