2003 Suzuki RM 125 - Answered Questions & Fixed issues

It is highly unlikely the gearbox will mount in a 2003 frame without modifications. The crankcase part number for the '94 is 43860. The '03 number is 36890. Nine years is a wide span and many changes have taken place. Sorry.

Your black ignition box may have gone bad. Or your stator plate came loose and changed your timing.

the way you explain this, the fuel and air mix is wrong, is the spark plug wet, if it is check the carb air mix screw. remove the mix screw and use a can of air and blow it out. before doing this remove the air filter and the spark plug then spray some wd (brand name) in hole and do again with the air can. then screw back in. leave the air filter off. and put spark plug back in and start the engine you will need to adjust the screw until you can get it to start. when it does give it a few good revs and keep it running for a bit. replace the filter and start engine and you will need to adjust the air screw till the engine sounds right again.

if knocking, ill bet it spun a shell, and they are a swine to time in, if high miles find another motor. ad use yours as spares.

http://www.carlsalter.com

check ur compression dry and wet to see if u have bad rings oil will blow by if bad if ur wet reading is higher than dry. bad rings

Are you using the correct 10W40W wet clutch motorcycle oil? It has special friction modifiers in it for this clutch drag issue.

On the right of the engine crankcase (as sat on the bike) there is the oil filler cap. Further down under a pipe is a drain screw. This is what you are looking for. Numbers 6 and 14 of the attached (hopefully) link. http://www.bikebandit.com/oem-parts/2003-suzuki-rm85-rm85k3/o/m147673#sch267790

You have a sticking float in the carburator, due to old gas, or dirt. The float moves a needle that turns on and off the flow of fuel into the carb bowl.

If it got realy hot you may of warped the head or cracked the cylinder. Do a compersition test to see how much pressure you are looseing. High would be the head witch would be easyer and cheaper to fix low you may need to replace the cylinder

The power band is the point wheneverything is nominal and and peak performance is realized. The air/ fuel ratio , timing, rpms It's mor predominant and noticeable in a motorcycle because of handling and weight All engines have them and these "power bands are really the peak of what s also called the torque curve Band meaning sp[ecific point and duration everything is working together. a gas lawn mower engine is set up to run inside this band. Thats why it doesn't fall on its fsce on the first patch of grass.
A diesel engine has a specific rpm range it has to maintain under load to get nominal horses.. If everything is functioning at nominal, max power is put out. Surprisingly enough it can be felt in all engines if paid attention . That's all it is, no special "bands" or parts. Knowing where the power band(range is makes a big difference on any machine. On an electric motor peak torque is @ let's say 1850 rpms. go faster useless lower toyque. go slower power drops To keep the range of the power band constant. everythinhg needs to be constant, like fuel mix, spark plug condition ,air filter andcarb adjustments.. I had a bike I hate and feared the power band. I would fall into it not paying attenyion and it would litterally crawl out from under me. All it is is that narrow band of peak performance..

Probably just a fouled plug. Pull the plug and ground it on the head. Kick it over and check for spark. If you have spark just change the plug and try it.

What model???
Almost all dirt bikes are 32:1. and then jet to get a brown colored plug.

http://www.thumpertalk.com/topic/686326-rm125-spark-plug-options-sub-for-r6918b-8/ Have a look at this link

check crank bearings. could be bad,if so it will suck air.

Air set at 2.1/4 turns from soft seat.

Jet 2 step above standard ex: if you are standard at 110 go to 112.

meetering passages are still abstructed need to boil carb in hot water and use carb cleaner and hi pressure air again if air screw are cap on your model find them remove cap and air screw also need cleaning.Mr Cee's cycle and atv repair.

without the parts in front of me i would say IF they look the same they may marry up, rule of thum is only replace cases in pairs.Or could you have the case welded?

side stand switch? dirty fuel /water in tank / carby