dan williams

Ah good info. Idle speed wandering is often a symptom of running lean. Have a fire extinguisher handy just to be on the safe side. Try spraying starter fluid around the intake boot to make sure you don’t have an air leak. WD40 used to work as it had propane (can’t write that without hearing Hank Hill in my head?) for a propellant but I’m not sure if it still does. Short bursts while the bike is running. If the idle changes then you have an air leak. Gotta be fixed before any jetting will make sense. As for the knocking, Betas are famous for needing high octane. The come down knock is very common, especially that era bike. You may get rid of the knock by jetting it rich but the power gets all lazy. If you have access to race fuel or 100LL avgas give it a try. Even premium pump fuel is a crap shoot and I won’t use it after some painful get offs from a crappy running engine. I’ve run VP C-12 for years. It has the advantage of consistency. Day after day the engine behaves the same. Something that just doesn’t happen with pump gas. Another thing to consider is a set of rings. Pistons and bores on trials bikes last a long time but a set of rings will give you back engine snap you didn’t know you were missing. Another thing new trials bike owners often do is mix the oil/fuel like a motocross bike. Most trials bikes are happy at 80:1 and some will mix at 100:1 if they’re real plonkers. The Vertigos are running 200:1 but I think 80:1 is the sweet spot.

I’m just learning with the rest of you guys.? Everybody whose added to this thread has provided insight and now we know the Barnett plates will work on the 4t. Thanks to Ward for being the guinea pig.?

Ok Billy the holes to lighten the floats made me laugh. Basssound OK, I just had to make sure. Betas turn the tightest of any bike and reward good technique but will punish bad technique and pushing the front end is a common complaint. The first thing must new riders will assign blame to is the engine/clutch. They can be a contributing factor. Especially the clutch (see clutch thread pinned to top of forum) but the usual issue is just lack of control working engine vs clutch vs rear brake. Add to that most new riders will try to steer with upper body and weight distribution and though you may cobble together a working riding style the fundamentals are wrong and will limit progress to a certain point. Watch videos of good riders and note how they keep their torsos forward and steer by bending the inside leg and arm while straightening the outside leg and arm. Even the top guys will only de-center to start a dynamic move and get their body re-centered as quickly as possible. You’ll hear a lot of BS about weight the inside peg or the outside peg in various terrain. Ignore it. If you weight one peg without the intent of changing the attitude of the bike you will have to counterweight the opposite bar to keep the bike from flopping over. You’ve now induced torsion in your body that limits your ability to respond. Rule one: Stay centered. Rule two: Steer with your feet. Rule three: Think pressure not weight. Rule four: See rule one. If you can find a copy of the Bernie Schriber/Len Weed book Observed Trials buy it and give it a thorough read. It may be old but the basic instruction in it is as true today as it was when it was written. You’ve just started and have much to learn. I’ve been riding trials bikes for >35 years. I also have much to learn?. But damn it’s been and continues to be a fun journey.

Wait a minute. Did you mean the travel adjust tang was pointing to the bottom of the carb? That is where it’s supposed to go as it limits the float travel while the carb is bouncing around. If that’s the case your float arm is now in upside down. We need pictures?

That's a little disturbing.

Sorry to point out the obvious but that's why you practice it. In Bernie Schriber's book he says, "Don't practice what you like. Don't practice what you do well." Braking on off camber turns is difficult. and takes time to develop the reactions that help you re-center as opposed to throwing your ass down the hill. The transition from up to down is one of the hardest to learn because it requires very fine control as the steering geometry and force on the wheels change through the maneuver. It greatly amplifies the jerkiness of the brake response. Especially the front. Same with the down to up transition which is very sensitive to throttle. Sorry, I don't mean to sound like the guy in the old joke. A guy with a violin case walks up to a stranger in NY city to ask directions, "Hey mister, how do I get to Carnegie Hall?". The stranger replies, "Practice, practice, practice."

You'd love a set of carbon fiber reeds. Makes the bike an absolute tractor without sacrificing the power anywhere else. The only non-compromise mod I can think of.

Noodle on throttle cable is loose on purpose so the cable can swivel. The brass tube on bottom of carb is float bowl overflow and it's important it ends below the float bowl. If you put a long tube on it higher than the bowl and the float bowl overfills it'll end up in the engine. The air screw at 1 3/4 is about right but you may have to adjust for conditions. The 27.5 pilot is kind of the default as the older bikes came jetted a little rich as opposed to all bikes now that seem to come jetted lean for emissions. The Billy T fix of nippering a hole in the vent tubes above the height of the float bowl works well and should preclude the necessity of routing the vent tubes up higher. In fact once the tubes have the holes above the float bowl the ends should be routed as standard down the back of the engine cases. Adjusting the tangs on the float lever is not always as straight forward as it seems. The travel adjust is important but the level adjust needs to be thought through. I assume you set it level when the tang just touches the float valve plunger. If you let the weight of the float assembly sit on the plunger it'll compress the spring in the plunger and give an incorrect level reading. One thing to consider is that with a slightly off pilot mixture most people will adjust their idle higher. So when they change the pilot they readjust their idle to a similar RPM but the slide is actually in a slightly different position. You nay need a slightly higher idle with the current jetting. Keep working on it. Carb adjustments take time and many iterations to get right. Well worth it.

The fan needs about 10A available to start so what the voltmeter reads with the regulator unloaded may not be a fair representation of the current available to start the fan. Also the electrical connections and the switch itself must have a low enough resistance to provide the instantaneous start current. Make sure your connections and ground are solid and below 1 Ohm. Failure to provide enough current can cause the fan to be iffy about starting. When running it only requires about 0.5A

Possible the primary ratio is different but I suspect the flywheel helps as once you get that mass moving it helps get you over “the hump” of the compression. Funny thing about my current 300 is some times I can stand on the starter and it won’t move and sometimes a quick stab spins it over. Usually when warm. At the end of the day though the electric start TRS looks better and better. I did add two teeth to the rear sprocket.?

There are ways to slow down a 300. Low compression head, flywheel weights, slow throttle tube... In the end it’s still a 300 and can be tiring to ride if you’re not in shape. Just kicking the beast can be a chore when it’s cold. The advantage of the displacement though is massive torque at low rpm. Does anyone need that much is the question. Typically no, as an old guy, you’re going to get your ass handed to you by kids on 125s. Having said that I’ve always had 270-300 Betas and love the bike I have now but it’s got some heavy modifications to keep it from trying to kill me. A low compression head and carbon fiber reeds have calmed the engine considerably. A modified clutch pack and less spring preload spacers give me super easy clutch pull and progressive clutch actuation and a custom shift cam has helped the shifting immensely. I have the fast throttle tube and no flywheel weight as I hate the “run on” that comes with heavier flywheel. Still hate kicking it over cold though. So can you live with a 300? Sure. The same way you could live with a 22 year old supermodel. Is it a good idea? Probably not. One of the most popular options around here is the 200. I’ve ridden several and out of the box they’re wonderful sweet little bikes that are very capable and very forgiving. You have to be more deliberate with the 200 but that’s actually good for your technique and you’ll spend less time on the ground. I expect a chorus of “Boo, don’t listen to him. Get a 300!” from the peanut gallery. Just remember all the times “friends” have talked you into things and how much help they were dealing with the consequences.?

I think you’re in violent agreement. The torque (force applied) is the same but horsepower is work done which has that load component to it because the wheel is moving further for the same force. So the horsepower is also the same as it can result in multiple transfers of energy. Acceleration of the bike + wheel spin (throwing dirt backwards uses energy) + mechanical losses (clutch slippage being one component). I think that the only missing piece between you is where the horsepower is expressed, rear wheel vs crank. It’s a common mistake to apply static analysis to a dynamic system and that is what Billy is saying. Torque can be static but horsepower requires motion.

Here’s mine.

Experts tend to like their clutch to hit immediate and hard like an on/off switch. First things first though. Pull the lever and the rubber dust cover off to make sure the piston in the master is actually returning to the snap ring. There is a spring above the piston that can be damaged if the lever takes a hard hit. Looking at the photo the adjustment screw should never have to be that far out so that looks funky but maybe those levers are not the correct ones for that bike. People that have measured the throw of the pressure plate report it to be around 1.27mm so there's not a lot to play with. Theoretically the hydraulic clutch is self adjusting as the slave piston only comes back as far as the pressure plate pushes it so its resting position is variable depending on wear and manufacturing tolerances. If the actuator assembly is put back together wrong it's possible the clutch will still seem to work but not work correctly. I think we've all lost the ball bearing that sits between the push rod and the actuator at one time. Replace it with a slightly different bearing and the clutch behaves a bit "odd". Along that line the Japanese video you're referring to uses shims to take up any slack in the actuator mechanism so that the clutch actuation takes place without any slack in the throw. This is to address the problem of clutch drag with the lever pulled in. Referring back to the 1.27mm of pressure plate throw, if you pull the lever at the handlebar all the way in and the piston in the slave cylinder moves 1.4mm over the entire lever travel that is a fixed amount. If the resting position of the clutch actuation mechanism has 0.5mm of slack in it you will only move the pressure plate 0.9mm which may cause some drag as the plates move past each other. If you use washers to take up the slack in the actuator mechanism so there is no slack then you get the full pressure plate movement of 1.4mm and less drag. These are numbers just for illustration, not actual measured values. Bear in mind that free throw at the lever is not necessarily the free throw of the actuation mechanism. The master cylinder must have dead space in its throw to allow the bleed hole in the reservoir to be uncovered. That part of the travel has no effect on the pressure plate as you noted. Since an expert had the bike I wonder if it could have an accessory slave cylinder. Might be worth asking if you can. One other thing I think worth noting is on my bikes I ditch the thicker plates on the ends of the clutch pack for two more of the 2.7mm plates. I just like the feel better being a duffer with no expert ambitions. Or intermediate ambitions for that matter.? Having done the clutch fix on so many bikes I have a stack of various Beta clutch plates in the garage. Some of them given to me by people who thought they needed to replace their plates. In theory it's a really simple mechanism but in reality they can be very finicky if the bits aren't all in the right place. This is where I wish all you guys were local so I could see it in person.

As strange as it seems having the clutch slip a bit on the road in top gear is pretty much not an issue as it is not a road bike. Having a progressive engagement in a section is much more important. Having said that if it really bothers you changing the oil to ATF may help as ATF has friction enhancers. The other thing to try is to take fine emery cloth and dress the steel plates to break up the surface polish that happens to the steels after years of use.

Any update?

If it’s a four stroke they are all six nominally 3mm. The two stroke uses two 3mm and four 2.7mm. Plates don’t wear on a trials bike and certainly shouldn’t be worn on a 2018. I think your adjustment is just out. To make it engage further out back out the screw on the lever that pushes the master cylinder piston in then adjust the screw on the perch to allow the piston to return all the way out to the snap ring in the master cylinder. I also move my levers in on the bars to give me more leverage and better feel since I only use one finger on the clutch and brake. It has the added advantage of making it hard to bend or break a lever since the bar ends will almost always hit first.

Ah I was wondering about the name change. Good luck to him. I always liked Ryan.

Has he sold the business?

I think the bikes in the UK all came stock with the flywheel and had a spacer for the case. You might be able to source one "over there". https://www.splatshop.co.uk/s3-beta-flywheel-weight.html Looks like Ryan's got some. Pretty thin so they might not need a spacer. Best option is to just call Ryan and ask. https://rypusa.com/s3-evo-flywheel-weight-14/

I might as well post this again. This is my diatribe on the cheesy system ground on my '08. It may be of some use to you. Beta_wiring.pdf

Voltage and frequency varies with engine speed but it has to be minimum around 15-16 volts RMS since there’s some drop in the regulator. I think it probably runs between 15-25 volts. The voltage will also be affected somewhat by the load.

H Hopefully. I put a new rear caliper on the '18 last month because the rear was acting strange after a hit. Replaced the bent disk but it still acted funky. Old caliper is still on the bench waiting to be disassembled and geeked at.

Got a few parts I could farm out. They come with no warranty, implied or explicit. All are the reverse bearing design so the bearing sits properly on the cam. The 13mm bearings are for the stock cam. The 16mm bearings may work on the 2018 factory and 2019 standard with the new cam design but I can't be certain as I don't have one to measure. The 16mm bearing does work with the custom cams the 12mm hole that the pedestal of the shift drum sits in is kinda snug due to machining tolerances so I had to hog them out to ~12.07mm with a sanding drum. Not precise I know but it worked. The green ink on one index hole is the position to put neutral between 1st and 2nd. The custom cam and 16mm bearings are now in my bike and one other "Beta" tester. So far he likes it.

That wiring drawing would typically be all you need to make your own but I've found the Beta diagrams to have inaccuracies. You could try one of the bike breakers in England. There'll be nothing in the US since most riders here just pull the headlight and other wiring off and lose it somewhere in the garage. Easier to schedule tea with the queen than get a trials bike road registration here.