Question about 2003 Yamaha YZ 125

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Yz125 2001 gear assembly. i have recently split my case and im just wondering how to make sure my shifter drum is in the correct position i have each of the 3 shifter forks put into each groove in the shifter drum and im just wondering if some one could explain to me if i have done it correct? thank you for any help.

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Pretty much impossible without writing a book, but basically if you can cycle the drum through the gears as you rotate the crankshaft without any binding then you likely have done it right. I have done this job hundreds of times and I couldn't explain the details if my life depended on it - not without having one torn apart in front of me.

Posted on Nov 11, 2010

Testimonial: "thank you ill needto put the case back together just to see if its working and if so then ill seal it and rebuild the rest back up"

  • mxtras
    mxtras Nov 15, 2010

    Well - you can rotate through the gears with the tranny assembled in the one case half without putting the other case half on, but the thing won't shift or rotate very smoothly.

  • ryan-dundas Nov 15, 2010

    ye athe gears are fine i think but the engine wont start and i dont know wats wrong because ive set the timing up according to manual and ive cheched for a spark and there is compression, i have no idea wat is wrong, i have took the top end off and looked at it and there doenot seem to be anything wrong



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Buell blast clutch position

The Blast Has a slip style shifter assembly - which means that it DOES NOT have teeth that grab the shift shaft that comes out of the case. Instead it has a aluminum 'drum' that the shifter clamps to. This 'drum' allows the shifter to slide up and down on it until you find a spot you like and clamp it down. Since the shifter lever doesn't have any teeth it can slip on the drum. the drum has the teeth and it also goes in between the shift shaft and the shifter lever. It is the ONLY bike I have ever seen with this style of shifter too. Make sure the shift lever isn't cracked or has ANY oil on or inside of it. It will cause it to slip. Another thing to consider - if you had a bent shifter - that means that the shifter hit something very hard. That could also mean that the shifter might have transferred that shock into the transmission causing internal damage.

Apr 13, 2014 | 2001 Buell M2 Cyclone

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Im rebuilding the transmission on my 82 rm250 but im not sure what the correct positioning of camshaft to gear shifter is any tips to get this corrected?

Hi, do you mean shifter to selector drum? When you fit the gearshaft into the gearbox so the return spring is located corectly in the crankcases, you will then hook the gearchange lever behind the selector shaft cover in any position as the spring will return the lever in order to select the next gear

Jul 31, 2011 | Suzuki EC300 Motorcycles

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I have an 04 yz 125 that won't shift into 2nd but

2nd gear is at the bottom of the shafts if the tranny is stacked in the mag side case. So it is controlled by the bottom fork. You should be able to shift it thru all the gears by turning the shift drum. Make sure as you shift the shafts stay all the way in the output shaft and idler shaft bearings. As you shift it, look for full mesh between the wheels(shaft that goes to the clutch) and the gears across on the output shaft.
If that all looks good, the shifter cluster(on the end of the shift drum, with the 2 dogs that engage the notched wheel on the end of the drum) may not be lined up properly. If the gears and shift drum are new, I'm thinking I'd look there first. Good luck!

Jun 11, 2011 | 2004 Yamaha YZ 125

1 Answer

Needing a service manual for 2004 883 xl. money is tight and I need to split cases to repair shift assembly and shifiting forks

On your Sportster, you don't have to split the cases to repair the shift assembly or the shifter forks. All you have to do it remove the primary drive, (primary chain, engine sprocket, and clutch assembly) and the front belt pulley from the other side.

Then, there are four bolts that hold the access door of the transmission behind the clutch assembly. Remove these bolts and pry the door and both shafts of the transmission out.

I've never seen a problem with the shifting forks in ANY Harley transmission. I may have just been lucky but whenever I worked on transmission shifitng problems, it was always something else. Why do you think you need to pull the transmission. Odds are, your problem is in the shifter pawl. These are notorious for giving problems. Unless of course, you blew second gear trying to speed shift it.

Good Luck

Sep 09, 2010 | Harley Davidson XL Sportster 883...

1 Answer

Wont go into 1st or 2nd, but will shift up to 4th and 5th, will sometimes go into netreal when riding, it has just had full motor rebluid, is it the slectors? when motor was apart all gears were good, and...

Take it back to the shop/mate that rebuilt it and get them to fix it.Or if you did it make sure the shifter drum is in the correct position and the selector lever is functioning correctly.Failing that you'll have to go back inside and check correct installation of selector forks.Make sure the tranny is functioning correctly BEFORE you put the other half of the engine casing together by spinning the outputshaft and going through ALL the gears turning the drum. Hpoe it all works out good for ya ....

Nov 15, 2009 | 2003 Yamaha YZ 250

1 Answer

Have no 4th gear for some reason motor running strong and all the other gears fine could it be the selector

Most likely shifter pin in shifting drum is broke, the only way to find this out is by pulling right side covers and looking at drum and linkage. If all pins are in place it will require cases to be split as it could be something wrong with the shifter fork and drum.

Aug 27, 2009 | 2006 kawasaki KX 250 F

1 Answer

Shifter noise on my 1985 sportster

The Sportster has a "cassette" type transmission. The transmission can be removed without the necessity of splitting the cases to get at it like most other motorcycles.

To remove the transmission one must remove the primary drive component that include the compensator sprocket, the primary chain, and the clutch assembly on the left side of the engine. On the right side of the engine, you'll have to remove the rear brake master cylinder, the front chain sprocket cover, and the front chain sprocket.

Going back to the left side of the engine and remove the four bolts that hold the transmission front plate (access cover) to the engine cases. There are two "pry points" on the access cover. Look around the edge of the cover and you will see them. Pry the access cover off gently and the transmission will come out of the engine cases. The shifter shaft will remain in the cases. When you reinstall the transmission, mark the shaft in such a manner that you can tell what position the shifter shaft finger is pointing. It should be level pointing to the rear of the engine as the transmission is reinstalled in the case.

If you can find a Clymer's manual #M428, it explains in detail the removal and repair of the transmission.

Jul 08, 2009 | 2004 Harley Davidson XL 883 Sportster

1 Answer

Suzuki 125rm manual

Find a manual by Googling " Motorcycle service manuals "
or go to

Installing new crank bearings is not a simple task. you will need a 3/8" impact driver, flywheel puller, case splitter and torque wrench. The top end comes off then the side cases, flywheel, flywheel electrics, clutch, shifter shaft, Crank drive gear and output shaft sprocket.

Split the case leaving the gears on the shafts and the shift drum and forks in place but out of the gearbox. Remove the crank and then remove the bearings from the crank or from the center casings depending on where they decide to stay when the case splits. Remove the crank seals from each center case half. Install new seals then install new bearings into the center casings.

Now just put everything back together.
By the way, now would be a good time to stick in a new output shaft (sprocket) bearing and seal. Be sure the OHC is timed correctly when installing the cam chain. Bad timing = bent valves.

Please rate this answer. Best wishes amcampailla

Mar 14, 2009 | 2003 Suzuki RM 125

2 Answers

My sunfire is not shifting properly....

I had a similar problem except i could shift to first and third and fifth but not 2nd or 4th or reverse. the only thing that came to my mind was new transmission but that is not the case. It was a way i could but it was so frustrated. I am certain it is the shifting cables. The name of the part you need to get is TRANSMISSION SHIFTING CABLES. Only the dealership has them, about $200.00 got them and installed but a certified mechanic. I have no problems shifting into any gear at all. Hope this information helps. Any info contact me at

Aug 26, 2008 | 1997 Pontiac Sunfire

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