Twin Shock

What year model is your DT 100.

Completely disassmeble the carburator and clean,and then clean somemore. I don't know if you have "Berryman" parts cleaner where you are but it does a great job on removeing dirt and varnish deposits. Replace "ALL" the rubber "0" rings and seals and re assemble. Hopefully you don't have a problem with the CDI but take care of the carb first. Also make sure the airfilter is not dry rotted and your sucking it into the carb.

Sounds like it is still not getting fuel, did you turn the petcock to the off position. Pull the gas line going to the carburator and make sure you have fuel reaching the carb.

Yamaha will still carry some parts for the bike, then there is E Bay.Speed and Sport also carries alot of NOS Yamaha parts. Sounds like you need a new ingnition switch for your lights to switch on. Someone must have unplugged the switch for the engine to run.

I have a WR 250 R and really like it. The WR 450 is not street legal in the USA.

First of all we need to ID your bike. If it is a 1973 you have a CT3, They changed to the DT in 1974. In the US the CT was gold and the DT was blue. Do you have a picture.

I agree,that does sound low. Just posting numbers I found.

I have seen claims from 15 to 28 claimed HP.

Lee, I would go back the the carburator and replace the "O" Ring on the Neddle jet (main nozzle) this little "O" Ring is very important and must be in good condition. The bike will not rev if the "O" RING is not sealing. This is a easy start to finding your problem.

Motorcyclecarbs.com has the kit.

Replace the air filter to the carburators, If the tank has been sealed install inline fuel filters, change the engine oil. If the oil seals have not dryed out you should be ok. After you get the engine running have the valves checked, or before.

Progressive makes shocks for the bike and there are thermal flow shocks just like on your bike on E Bay all the time.

I need to know the year model of your bike and I can help you.

If the autolube system has been removed you should mix at 32 to 1 ratio.

Fast Bike.

Guys, check out Yamahaenduro.com The September bike of the month is a 1979 DT250 for your pictures and anything esle you need can be found there.

The 1982 YZ 250 in the US was liquid cooled. Any air cooled model YZ, IT engines have differences as they were designed for different purposes. They will interchange frame to frame from the same year if that is what your looking for.

I can on reply for the US MODEL. The engines are totally different. The YZ in 1982 was watercooled. The transmissins ratio's were wider in all IT's

You chain and sprockets are completely worn out, I would not ride the bike until they are replaced.

I can only speak of the US models.

The standard sprockets were 14 T on the counter shaft and 45 T on the rear wheel.

If you really want to do this I would suggest you buy a parts bike and use the wiring harness, voltage regulator,ingnition coil,stop switch ect....... and you must have a 12 volt battery for this engine to even run. The at series enduro's are 12volt to power the electric starter.

Mark, you need to join Yamahaenduro.com There are absolute experts there on you particular bike and more.