I have a rm 124 every time i change gear its just KEEPS SLIPING

Hi, it sounds like your clutch friction plates have either worn out or, someone has put the wrong oil in it, some car oils make the clutch slip in high gears.

Check the fluid, with the motor in park.

Dodge has had a problem in the mini vans for years with there transmissions Sliping in different gears,You will have to take it to a tranmission shop to get them to road test it to see whats wrong.

Web search "bicycle chain slipping" to help narrow down the cause. Likely it is worn chain, gear teeth or both.

Then web search what you noticed.

A great resource....
http://sheldonbrown.com/chains.html

im having the same problem with my 2003 rm 125, tombones49 is wright about the shift forks.

The slipping is usually an actuator. However a bad gear in the motor could cause it. You have to thoroughly check both before you can be sure

cluch sync is out. Are you rpm shifting or using clutch always? Bent or burred gear slider

oh dear? its the auto box, the cluches are sliping and getting very hot if its full of aft fluid and still sliping i think its going to be a rebuild or replacment box now i realy dont thing looking at the velve block is going to be of any help to you,

your loking doggs on you gears inside your gearbox are rounded and they wont lock into place.. there fore it jumps out of gear when its under load... so you need to split your motor/gearbox replace the damaged gears and most likly your selector forfk as they will bent bent.. costly excersize $900- 1500 job to get done... too many burn outs or power shifting not using your cluch... or lack of oil changes can cause this [email protected]

Is it Manual or Auto transmission ?

If Auto, have you checked your transmission fluid level ?
Do this first !

Good luck !
John.