dan williams

Well there are limits to the speed a rotor will go without tearing itself apart. Also at very high speeds balance of the stator becomes an issue. For the stator there is a fundamental limitation of the inductance of the coils. You simply cannot go above a certain frequency and get enough current into the coils to develop a rotating magnetic field. That is why higher speed motors have fewer stator poles. Torque is highly dependent on the magnetic coupling between the rotor and stator magnetic field so fewer poles means less efficient coupling and less torque. If you ditch the permanent magnets and go with a squirrel cage rotor you are also limited by the inductance of the rotor and the need to have a slip to keep current flowing in the rotor. Fun stuff to think about for an engineering geek (me). I'm curious GWHY how many rotor/stator poles are you running and do you change the number of energized poles to compensate for bandwidth limitations for high speed operation? Imagine what you could do with a room temp superconductor. You could build a stator with single wires instead of coils. Ooh even better, thin film graphene. Print the rotor on the inside of a ceramic cylinder. Ok I'm geeking out badly now. I'll stop. How well does a rotor spinning at 10k RPM handle the normal jolts of trials riding? Oh and understand that as someone who respects doers above all I ask with honest curiosity as you've actually built electric bikes and that impresses me no end.

Allen key with the short side cut even shorter works for me but it's still a pain.

Sadly you won't know without pulling it apart and them you might as well do a proper repair by replacing gaskets/o-rings anyway. Yeah a leaky head gasket will pressurize the coolant system (more than normal, coolant is usually under some pressure) you may also notice oil in the coolant.

Ah now I see. Yeah that is a little odd. Almost like a high spot on the crank caused by a casting defect in the steel. I'd love to throw that under a microscope.

Looks like overspray varnish for waterproofing that just aged from long exposure to heat. That's unusually clean compared to any engine I've been in.

It's not all that hard. Just be careful and take it slow.

If your air screw is all the way in it's probably time for a disassemble and clean of the carb. With the air screw all the way in the bike should bog badly off the bottom. If it seems to run OK with the mixture screw in all the way it could indicate a blocked pilot jet. A lot of times riders will just crank up the idle speed but it makes the bike harder to ride in the slow stuff. If you pull the carb pay close attention to the pilot jet circuit. Pull the whole carb apart and use compressed air to blow out the jets and carb body. Note which jets are installed. The typical pilot size used around here near sea level was a 27.5. Stock was a 30 but the suspicion was always Beta put that in so the bikes would break in with the slightly richer jet off the bottom. There's also considerable information on stopping the fuel piddle problem of the Beta in the Mikuni thread pinned in this forum. My preferred method is to just nip a hole in the vent tubes above the float bowl. Also look at setting the float level and the float travel. This is done by adjusting the brass tabs on the float lever thingy.

It was a warning given in genuine concern for your safety. Respect it as such. Took me a second to think what ali was too though.

To stop the siphon just nipper a hole in the vent tubes above the float bowl. No need for modifications. As long as the hole is above the level of fuel in the bowl the siphon stops.

Glad it helped and welcome to the sport.

I've got the one size up front and rear on my '13 EVO. Works fine for my 100kg lard ass. Preload is different than spring rate. If you crank the preload up you have to have that much weight on the bike before the suspension moves so you lose all compliance up to that point. Imagine going down a steep hill and the weight transfer moves to the forks. You now have a hard tail in the rear. Very nasty. A heavier spring with less preload will usually have some compliance in the same situation. Oh yeah, got mine from Steve Saunders too. Neat to order a part and get a confirmation email from one of your heros.?

A leaky head gasket will show some evidence of oil in the coolant as the high pressure in the combustion chamber drives air/fuel mixture into the coolant. You should be able to see this when you drain the coolant into a clean container.

Ok did it run OK before it overheated? No pinging or detanation? Over heating can be caused by several things. Too lean a fuel mixture due to blocked or incorrect jetting. Ignition timing too advanced. Too low an octane fuel. Carbon buildup in cylinder head. Too little air flow through radiator. Too little coolant flow through cooling system. Failure of coolent system to pressurize due leak. The possible foot causes are many but narrowing it down shouldn't be that hard. If the engine runs good until it overheats then it is likely a cooling system failure rather than ignition and/or fuel. Your fan runs so check your system for leaks and make sure your impellee is spinninig and in one piece. I don't know about the Shercos but the Betas are known to shred impellers and have porous cases in the waterpump area. Coolant mixture has some effect but even running pure water in a system will work if the system is operating properly.

This has been reported as one of the early symptoms of a stator going. Usually the trigger coil goes bad causing the timing to shift. Another possibility is your flywheel key has sheared causing your timing to be off. I've seen this on Beta's but I believe the Shercos share some very similar electrical components.

Just a guess but I'd say it's because it's full of fire. If you have a pinhole leak that depressurizes the coolant system it will boil the coolant. That's because parts of the coolant system operate over 100C. Definately the head will be that hot. So the rough equivalent is like boiling water on the stove and picking up the pot by the sides. If the engine is not sounding like a can of marbles being shaken it's probably within the correct temp range.

One thing that made it special was the craftsmanship of the photography. It really was a beautifully shot show. There was so much detail in what was done. Maybe that's the same but it wasn't the only reason to watch. If it wasn't for Top Gear I wouldn't have recognized the F-type Jaguar I saw Saturday. I also wouldn't have driven a 458, Mp4-12C, GTR, Gallardo, Aventador and 991 GT3 nor would my wife have driven a Super Leggera, AMG Black SLS, 991 GT3 or Hurrican. The boys made it look so fun that I not only got the jones for (short, expensive) bits of track time with these brilliant pieces of engineering my wife also found out she enjoyed it too. I understand the show was getting long in the tooth but I still loved it and later enjoyed the news section perhaps more as it was just friends doing what friends do. One problem with driving the super cars is I keep forgetting to look at the in car camera and yelling POWER! They sort of demand your full attention at full chat.

Despite it being scripted and rolling on many of the same ideas from years past there was the occasional bit where the friendship of the three shone through. The laughs were genuine. When Hammond was injured and the beeb pressured Clarkson to continue the series his reply of, "Not without my Hamster!" said more to me than any script. The fact that the other two left with Clarkson was that rarest of things, loyalty. The fact that the BBC was so cheap with a show that was pulling in so much money amazed me. An on-site production without catering is unheard of for most shows. Most production companies have a team of people to protect the stars from themselves but the BBC seems to have wanted Clarkson out and were going to do whatever possible to make sure he provided the reason. So they got what they wanted. I look forward to The Grand Tour. The promo of the three sitting around discussing the name of the new show was still funnier than anything Chris Evans has done.

Stewie said he didn't adjust anything. I gave it a squeeze and it's as light as my Beta with all my clutch work.

I don't see the need for an electric clutch. On a gas engine the motor has to be turning at a certain speed to deliver enough torque. So the clutch is used to modulate the torque stored in the rotational mass of the engine spinning at a high enough speed to have sufficient stored energy. With an electric motor a great deal of torque can be delivered from a dead stop limited by the type of motor and available current. That should make control much easier as applied torque is a single control rather than the combination of two very different motions. If you feel the need to synthesize a clutch with an electric motor you simply reduce motor current with the lever effectively decoupling the stator/rotor but you get the same effect from just rolling off the "throttle".

Stewie had the same TRS in Meriden and the clutch has lightened considerably as it has broken in. I'd say give it another try.

So where is the Dragonfly? Come on, you're killin' us here!

Got one in the toolbox. In the garage. At home, where it was no help at the time.

That was fun. Started bike up yesterday to ride an event and felt it was a bit boggy off the bottom. Went to adjust the mixture screw and it the screwdriver just kept going in. Looked into the hole to find the screw had bailed. Never seen that before. Now it has a Jitsie adjuster and that's harder to get to than the original. Time for the spring disassemble and clean on the Keihin. I think I'll cut a groove in the Jitsie screw so I can turn it without forcing my fat fingers in under, over and around the muffler.

I think I just invented a new version of MadLibs?

**** yeah! You tell that ***** Andy to ****** and ******* ****** with a ********* crowbar. ***** moonshot *******. And remember the ***** **** duck!