04 RM125 wont shift

I have a 2004 RM125, it  wont shift out of first. It will go into first and neutral fine. I have the clutch out and side cover off, where should i go from here? Does this sound more like a bad fork or a bad gear? Any help is appreciated!

2nd gear has blown in my 07. My guess would be a bad gear.

 

Mine actually goes straight from 1st to 3rd gear. Well, so the previous owner tells me at least.

I had a tranny problem with my 125 too. The best answer I could give you is look at the transmission. I know it could be a job but it is the only way you will find out.

Okay well i just got my other bike going so it looks like this will be the winter project. Im thinking about doing a complete rebuild while its apart, I dont believe this bike has ever had a bottom end rebuild and not sure about the top. Its an 04. Any of you guys done a complete rebuild and can give me an estimate of how much it will cost? Any specific things to watch when splitting the cases? I have a manual and light mechanical experience.

You'll be fine, split it laying it on the right side so transmission gears don't fall out. Lay everything out in order in which it came off the shaft. The manual will give you specs to go off of when measuring the shift forks. Look closely at the pins on back of shift fork that rides in the drum, they'll wear and bend. Biggest problem we've had are the shift dogs rounding off causing it to pop back out of gear. Take good quality pics and myself and others can help you.

 

I've been in the transmission 3 times in the past year on 2 bikes 06' and 07'. Some I'm learning myself but have been there done that a few times now. 

Before you tear into the transmission, always check the simple stuff.  Behind the right side cover is a fairly complex shift drum mechanisms with springs and finger followers (sorry, don't know what they are really called).  Anyway, shifting problems often can be traced to that mechanism.  You are going to need your manual to be able to check all the parts.  These parts are easy to access and repair, but you may need to find someone with an experienced eye to spot what is wrong.

Okay thanks, going on a riding trip this weekend with another bike so im just going to make sure it is ready to go and tear into this one next week.  I will look over the springs/etc. behind the clutch one more time and see if i can spot the problem!

Okay well i just got my other bike going so it looks like this will be the winter project. Im thinking about doing a complete rebuild while its apart, I dont believe this bike has ever had a bottom end rebuild and not sure about the top. Its an 04. Any of you guys done a complete rebuild and can give me an estimate of how much it will cost? Any specific things to watch when splitting the cases? I have a manual and light mechanical experience.

well a top end kit is about 125 bucks? correct me guys if im wrong. and a bottom end kit is about 200 if i recall? I havnt done a full rebuild in a few years so i can't exactly tell you. On my cr80 about 4 or 5 yrs ago we replaced all the bearings, crank rod and whole top end and it costed about 800. 

Okay I still havent found the time to tear into it, hopefully i will this weekend. Ill keep yall posted on any progress

have you looked at yourshifter pawl? mine didthe same thing, and i just had to re loctite and snug the screws that hold it in

Shifter Paw?

Shifter Paw?

the annoying little springloaded device that sits in your shift drum on the clutch side and meshes with the shift shaft.

I did some research on the shifter pawl and it sounds like that may be the problem. Glad i didnt tear it apart yet. Im gonna take the pawl out tonight and inspect it. thanks for the help ill let you know what i find

I did some research on the shifter pawl and it sounds like that may be the problem. Glad i didnt tear it apart yet. Im gonna take the pawl out tonight and inspect it. thanks for the help ill let you know what i find

a lot of time its just the screws are too loose

I just logged on to ask you how to get the screws out! Mine are not budging, my screwdriver slipped once so i just decided to see what you guys think. I don't want to strip them, any special tricks to getting it out?

The right size screw driver. A p3

Those screws are almost certainly held in with Loctite, and for good reason. If they ever rattle loose they'll raise all sorts of ruckus in there.

There's a couple tricks to getting them out.  The first one is definitely to use the right sized screwdriver.  Try heating up the screw heads for a few seconds with a small propane torch or something similar.  If you don't have access to one of those you can borrow your mom's hairdryer. Set it on high and hold there until the parts are too hot to touch.  That should soften up the Loctite.

And if you don't have one of those hand held impact screwdrivers, I strongly urge you to get one. They're like a very heavy bodied screwdriver handle that you can change the tips on, and there's a cam inside it.  When you strike the butt end it imparts a quick shock of a little twist in the tip.  They do wonders for removing stuck fasteners!  You can probably get one at an auto parts store for about $25.  Money well spent!

Thanks for the info, i know I have an impact driver but ill have to find it.

This bike has been on the back burner, ive been doing work on my truck and other bike and havent found the time to work on this one. Hopefully I can this week :banghead:

well a top end kit is about 125 bucks? correct me guys if im wrong. and a bottom end kit is about 200 if i recall? I havnt done a full rebuild in a few years so i can't exactly tell you. On my cr80 about 4 or 5 yrs ago we replaced all the bearings, crank rod and whole top end and it costed about 800. 

The price seems high... That's what I paid for full rebuild plus the cylinder head !

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