Yamahahahaha

[Ummagumma]

Maybe a question for a Yamaha quad bike forum but here it goes. I went for a ride in the forest outside sabie on a borrowed yamaha blaster. All of a sudden both back wheels locked up, I skid sideways like a drifting king and the engin died. From there I could not get it started, the engine seems to be seized up. Does anyone here know of spare parts at a good price as I need to fix the bike. If only their bikes were as good as their amps.

[XL1000]

Try www.wilddog.za.net register and post your question there. Will be far better received.

[ron g]

i'm not sure that you should feel obligated to fix it.

i really doubt that anything that you did on a short ride, would be likely to cause a seizure. (unless of course you had it for a long while & ignored warning lights.)

[mahleu]

It's a 2 stroke if you close the throttle then the engine stops getting oil.

If the engine has seized then it will need to be rebored and a new piston. Could you kick it over at all? If so it's not seized.

[Ummagumma]

It kicks over but its not easy. My wife used the quad to travel 500m to work in the morning (its the highlight of her day), we have been using it for about a week. My guess is that because the engine is air cooled the slow drive to work and back could have caused some damage to the engine.

[Bruce M]

It has an autolube oil system (or it should have if not removed/bypassed), this is most likely the problem.

This injects 2 stroke oil into the engine. If this system fails, or the reservoir runs dry, the motor will seize. The injection point is between the carburetor and the reed valves, so a closed throttle will not be an issue.

Alternatively, these autolubes are often removed/bypassed. If so, 2 stroke oil needs to be mixed with the petrol you put in the tank, if not the motor will seize.

If it still turns, but will not start you have probably broken rings. These are relatively easy to work on, so should not be that bad.

Sometimes they seize and then will run again after cooling down, with little apparent damage. Have you tried to start it and not just turn it over?

[Ummagumma]

I will give it a try when I get home. I tried to start it just after the incident and not again. I did bypass the tank with twostroke as I dont trust that system. I mix my twostroke with the fuel 40:1 but I always end up putting a bit too much twostroke in (not sure if too much can harm as much a too little...)

[Trompie67]

I will give it a try when I get home. I tried to start it just after the incident and not again. I did bypass the tank with two stroke as I don't trust that system. I mix my two stroke with the fuel 40:1 but I always end up putting a bit too much two stroke in (not sure if too much can harm as much a too little...)

You're running it lean at 40:1.

Yamaha 2-smokes are 32:1 on the air cooled motors (most of the liquid cooled as well). Remember, development on these engines stopped decades ago, so this is old tech, not like KTM who've continued development.

They are easy to work on to replace piston & rings, so long as the bore is not scored. Parts can be ordered from Rudamans in Nelspruit, they are the agents.

[Ummagumma]

The good news is it starts. There is a knocking notice coming from the engine so I shut it off. I know rudamans well I have dealt with them to fix my stihl pressure washer.