lemur

I made a whole bunch of assumptions including he changed out the oil to inspect it for shrapnel. What part do you figure exploded?

If the problem only manifests in one gear range, that supports the likelihood of it being one compromised shifter fork. The forks and a shift drum with detents to hold everything in the correct aspect are what collectively hold the gears in alignment with each other, if the gear faces don't engage correctly the whole thing locks up. Third is the gear I'm most likely to wear out on a decent powered trials bike ymmv.

I know the first thing I would do is to shift it up one or two gears and see if the problem persists. 1st. is geared too low unless your average speed is a crawl and there is nothing ahead of you. Worn or bent shifter forks is ultimately what makes a transmission change gear on its own etc. Why; because the shifter forks are made out of relatively soft material compared to everything they run against and because you can bend a shift fork just by crashing on the shift lever. Fiber optic inspection of the assembly is a possibility and might avoid a complete tear down if the parts reveal no damage. Common issue to all motorcycle transmissions because most are built the same and it's not uncommon to drop them on the shifter.

Fuel is leaking past your float needle and seat valve uncontrolled. Could be dirt, could be worn parts and it is a very common problem. Same happened to a friends Beta evo here just last week, he shut off the fuel and gave his carb a bump and the float corrected itself at least until he got home.

I can see that, would goop up the exhaust system if the oil isn't being burnt off sufficiently and I've had ipone do that. If you use a 2-stroke oil from a reputable company that says 100:1 right on the bottle that is a safe bet in my opinion and it won't goop up the exhaust much. If the oil makes no claim to being suited to lean mixture I tend to pay more attention to the service manuals.

The owner manual says 2% and that works out to 50:1 ratio so imho that would be a good place to start.

Terrific bike for winter riding if you stud the tires and have a heated garage to start out from and keep the brakes dry, any 4RT with studz is a blast to ride through much of the winter here. With grip studz in regular trials tires you run the tires about 4psi harder than summer, the tire needs to flex less in the freezing cold.

If you just had a constant year round source of fast moving water across your property a true green solution would be no problem at all 🤓 the greater challenge is having a charging station that suits the battery type without over charge, has heating and cooling and won't become a problem if it bursts into smoke and flames one day. So basically you are looking for a comfortable 4 season concrete power bunker next to a small river that flows across your property, a whole bunch of money to sink into equipment and then you can have free rides forever.

Giant teenagers have zero problem getting traction & they can really make a dab count because they can pick the bike up by the grips and throw it some distance if required 😐

Another giant teenager 😎 run the rear tire almost flat and the front soft enough that you only occasionally feel the rim, don't hesitate to rev it up lots, 4RT love lots of engine revs and just keeps pulling up to peak revs, fuel injection fires as reliable as the spark plug, never misses a beat, the 300rr has more power for carrying 3rd gear, the 260 needs to be rung harder to generate the same oomf and feels more at home in 2nd gear. 4RT runs reasonable well on straight pump fuel but pulls a little stronger in down low rpm if you run upgraded fuel. They flame out at around 800rpm or lower because there is not enough electricity to run the fuel pump that low. The bike rewards a steady throttle hand, you should resist the urge to 'blip' the 4-stroke engine as you would a 2-stroke, all that does is mess it up and you will never need to rev it up to clean out the engine just before a big hit, it's not necessary.

I'm sure there will be by this time next year, the name of the rider that I was extremely impressed with is Justin Brazeau, an accomplished Pro class MX and Hard Enduro rider.

4RT has a super broad power band, the fuel injection is what makes the engine perform so well. Montesa suspension feels more settled compared to TRS, GasGas and Beta that feel more lively. Montesa is great for long hill climbs and winter riding, great for deep water crossings and deep mud sections. Rear suspension dog bone requires more service than some because it is exposed to damage. Frame and swingarm is very durable in a crash, rear fender is expensive but way more sturdy then some.

Nice headlight, you should take that off and store it somewhere safe.

I thought they were all expensive 😐 Stay away from the Hall effect lanyard switch ones, go with a simple magnet one like Jitsie sells, they fail less often.

Might be best to post this question in the forum dedicated to ‘ACU discussion’ instead of ‘General Trials Talk’ Rider numbers in our club are assigned to you when you purchase your competition license.

Well there you have it then, the ideal kids bike is obviously what Gael Chatagno rode in the SSD 🤨

Wow that’s a lot of fuel, the overflow tube must be plugged or routed up instead of down, fuel would need to get past the reed valves and completely fill the crankcase, fill the scavenging ports and leak out past the crown of the piston. Check the carb overflow vent pipe first.

Had to google Gael Chatagno, that’s no kid, thats a really big adult to name drop in a discussion about kid size trials bikes. add: says his first bike at age 5 was a PW50

What kid size electric bike has a clutch and gears? And what electric bike that runs full size trials tires complete with a clutch etc. does not cost more than a regular modern trials bike 😂

From observation; the biggest problem with small frame trials bikes is the limitation to not run full size radial trials tires and rider size is a better gauge then age. Some young people get real big faster than others. Lots of engine power or lack of horses is less of an issue for most if it has a clutch and some gears, small frame bikes with minimal suspension and small wheels, electric bikes and automatic transmissions all limit the young riders ability to fully experience or navigate trials terrain.

Almost guarantee the fluid leaked down through the O-ring, only way it could evaporate to that extent is if you left the reservoir cap and rubber diaphragm off. The purpose of the rubber diaphragm is to reduce water from contacting the hygroscopic DOT fluid. Moisture on top of the diaphragm is water that has entered through the tiny vent hole and condensed. Vent hole needs to be clear or lower fluid level will create a vacuum in the reservoir.

Dry clutch master means the DOT fluid or mineral oil has leaked past the piston O-ring and into the transmission, its an easy fix but you need to use the right size and material type replacements.

Those are almost exactly what grip studz look like. Auger thread vs screw is what makes them stay in good. With grip studz the carbide tip is more apparent. Those would work great and if they are less expensive I would give them a go 👍

Close to that yes, once you add the tax, shipping and the special tool. Up side is they will last for many years. We ride the same terrain as in summer, the studs are wicked fun and great practice for riding over logs on any angle and really steep hill climbs ⛄️ I find most of the screws in spring and reuse them, the rest disappear into the ground because they are only about 3/8” long once you cut them to length.

Does anybody know the normal operating temperature of a 2-stroke engines transmission oil?