thats_a_five

I can't imagine that it is good for the chain or the frame to have them hitting each other. And heck, why fix a problem with an elegant solution when you can simply use a bigger hammer or cheater bar!

Make sure you buy the high temperature silicone O-rings. Regular bun-n O-rings are likely to go up in flames at the high temps on 4 stroke exhausts. If the leak is small, you could simply take it apart, clean up the surfaces and use some hi-temp silicone sealer when you reassemble.

Do you have the Domino throttle? Most people say to NOT safety wire the cable to the grip end. They are designed so that in the (rare?) case that a rider comes off the bike and it lands on the throttle end, you can simply grab the cable and yank it out of the housing. The cap flies off, the pivot wheel may fall out but when you let go, it allows the cable to go slack so the carb slide can go back to idle before the motor goes "boom." You might want to reconsider the safety wire. I know I did after someone smarter than me explained this.

Haha, missed the spelling. Good one.

Please be careful when using chemicals like methylene chloride and such. There are known hazards to skin, respiratory, and nervous system functions from incorrect contact. Google it and read the information about proper handling and disposal.

A thorn is a sharp spike that grows from the stalks of some plants. Think of a rose or cactus. Some of those thorns can be very sharp and very long. Some even have barbs like a fish hook so once they get into something, they just keep going deeper and deeper.

Just a thought. I see several people in the Montesa forum indicating hard, hot starting on 4RT's that were solved by proper valve adjustment. Might be worth checking your valve clearance? Good luck.

Have you seen Tire balls? Yeah, no joke. http://www.tireballs.com/ I have no experience with them. Just thought of them when I read about your problem with flats.

Remove the seat and air filter. Spray some starting fluid in the intake and give it a kick. Spark and fuel should at least make a pop or two. If so, then it is probably a fuel supply problem. You have drained all the old fuel, right? With fuel in the tank you should be able to disconnect the fuel line from the injector and see if the fuel pump is working. If it is, then remove the injector, reconnect the fuel line and see if the injector squirts fuel. If it is, and you have spark it should start. Let us know what you have done and the results you get. Good luck

Two words Zippy: Bark Busters

Welcome to the club of Ty250 owners and trials riders. For specific questions regarding your bike I would suggest in the Yamaha or Twin shock forum in this site. There is an active trials club in Portland. Google COTA or "Columbia Observed Trials." There are some great people in the club who ride vintage and / or modern trials. There are some awesome places to ride there as well. I am from the Seattle area, am a member of "Puget Sound Trialers" and also have a TY250A. Look forward to meeting and riding with you some day. Bill

An octane booster would certainly reduce pre-ignition (pinging or pinking). Pre-ignition usually happens due to one or more of 3 causes: 1) timing too far advanced 2) Too low octane of fuel 3) high compression.

I bought my '05 4RT this summer and love it. The rear suspension is awesome! Compared with your '97 it is a vastly better bike. Complicated? The frame, wheels and suspension are on par with any other trials bike. The engine is more complicated because it has a complete valve train where 2T's use reeds. But, its a Honda engine. Keep the oil fresh, adjust the valves once in a while and it will run forever. The fuel injection means no carb or jets to have to monkey with. In riding, I find it to be more suited to a flowing style compared with a newer GasGas that seems to be more of a point and shoot. I still say, ride several bikes and see what feels best to you. Keep your feet up and have fun!

What year is the Beta? The two biggest difference in 2 stroke vs. 4 stroke are: 1) How quickly the engine spins up. 4T is slower 2) Compression braking. 2T's don't have much engine braking so you can get off the throttle and coast. 4T's act like applying the rear brake when you get off the throttle. 4T's can sometimes get more traction that 2T because there is a power stroke on every other revolution with 4T. There are other differences so the best thing is to try several different bikes and see what feels best for you.

First thing to check is the timing. Remember that bike has points and a condenser. If you do not know that last time they were replaced it probably makes sense to replace them and set the timing correctly first. The leaded additive is intended to lubricate the valve and valve seats in 4 stroke engines so you really don't need it in the TY. I would check if the additive is flammable by itself. If it is not, then adding it will have the effect of leaning out the mixture. If it is flammable, it should have little or no effect on lean or rich mixture. More information will help us give you better answers. When is it making the noise? Idle? mid-range RPM? Full throttle? Acceleration or deceleration?

I had a similar problem on a Gasgas with an extra neutral between 2nd and 3rd. It turned out to be the springs on the shift selector. Once I replaced them with the newer stronger springs I never had the problem again. It looks like the Sherco has a similar set-up. I would recommend staring with replacing spings 9 and 12 on this parts breakdown (check to be sure of the correct year and model for your bike). Less than US $10 for the parts. http://www.nofives.c...arts_s/2031.htm

I have an '05 that I just got this summer. The rear mudguard is a one piece unit that goes all the way to the tank. I have not managed to break it yet (give me time) but I can imagine it will be costly for the part and also for the vinyl covering. Mine did come with a broken one that had been zip tie repaired. I may look at how I can mod the mudguard into 2 pieces so the rear can easy be zip tied on and off. The brake pedal for these does stick out quite a ways. at about US $60 each, I don't want to replace many of those. I have seen a couple after market ones that are much closer to the case. I have had one issue with mine when the brake pedal did not have enough free play. This caused the rear pads to drag and the brakes got so hot they started to bind the rear wheel. I have heard of others having this issue also. Simple adjustment in the shop. Otherwise the bike has been bulletproof. And a joy to ride. Still getting used to the compression braking after switching from a 2 stroke.

I used high temp silicone seal for over a year on mine. Worked fine.

When I had a 2 stroke, I always cleaned or replaced the plug the day before an event. I also carried a spare plug and tools with me when I rode. If the bike runs well with a new plug, it is unlikely that the exhaust is badly plugged. When the exhausts get plugged, the engine acts and sounds like it is trying to blow through a small straw and have significant power loss. A partially plugged pipe will cause a rich fuel/air mixture, which can lead to fouling.

I would start by checking your spark timing. It may be too far advanced. Next check the valve clearances.

Where are you located? Fuel in different countries is different. Example: in USA, highest octane available outside and airport is 92. Fuel in USA contains up to 15 % ethanol. There are some fuel stations in USA where you can buy ethanol free fuel. That is all I use in my bikes and power equipment anymore because of the bad effects ethanol has on plastic and rubber parts. Fuel in Europe can be up to 98 octane and no ethanol.

It would help if you told us where you are located. Here in the USA, the 50 states all have different rules about what documents are required. I can only imagine what is required in other countries around the world.

My buddy has a 300 Raga and he had a hard time starting it. His 20 year old son can start it in one kick. The key we found is it has to spin fast to start. Bike must be in neutral, get the piston to top of the stroke, then a fast stab with the foot. Make sure the kicker is engaged at the top of the stroke before kicking. Gotta spin fast!

I find that if I stall my '05, it can be difficult to start after. I also had a problem recently with the throttle cable pulling out of the fitting on the hand throttle just enough to crack the throttle open even when I held the throttle in the closed position. As you know, if the throttle is open at all, the bike will not start. Check that the cable end is fully seated.

Does the bike rev up before it quits? That is a common indication of a super lean condition as a bike runs out of fuel. Other's have suggested checking adequate fuel flow to the carb including sticking floats. Those are great ideas. Here is another more obscure idea. Are you losing coolant from the radiator? Perhaps it is an overheating problem. Trials bikes run very low amounts of oil per gallon (or liter) and very small radiators, compared with most street or trail bikes. Running at continued high RPM's can lead to very hot running inside the engine. This can cause a light seize. How do the piston look when you changed it? I have heard that during some of the world championship events with long road transits, the riders often ride with their choke on to make the mixture richer to provide more internal cooling.