Question about 2003 Yamaha YZ 125

1 Answer

My 01 yz125,with a Athena big bore kit- i just rebuilt the top end, took it easy with it for the 2 1/2 hrs i rode it...then i went roll up along side my freind and when i pulled the clutch the bike still inched forward about a couple feet and died out..didnt really think nothing of it. went to kick it and it felt like it was binding..sifted to neutral and could not get front sprocket to spin..had to carry rear of bike to move. please tell me it wont be too costly to fix, thanks for your time.

Posted by Anonymous on


1 Answer

Gregg Mahin

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    One Above All:

    The expert with highest point at the last day of the past 12 weeks.

    Top Expert:

    An expert who has finished #1 on the weekly Top 10 Fixya Experts Leaderboard.


    An expert that got 20 achievements.

  • Yamaha Master
  • 65,298 Answers

Hi, Anonymous I feel your pain you just dropped a ton of "DRACHMA" on rebuilding all or part of your engine and a couple of hours or days later it dies or locks up and you want me to tell you how much it will cost to fix. Unfortunately due to the magnitude of yesterday's solar flare the batteries in my crystal ball are dead and the circuitry in my mental telepathy headset was melted. Let me break it down for you.
1. Was the work done by an experienced trained professional technician or someone with good intentions that was not qualified to hold a wrench?
2. Was the proper break in procedure explicitly followed using the proper break in oil and changed as directed?
3. If your bike is used for off road abuse or competition there is no warranty in most cases.
4. If you have a street bike that had performance goodies installed no warranty in most cases.
For more information about your issue and valuable "FREE" downloads that you will need please click on the blue links below. Good luck and have a wonderful day.
Yamaha YZ125T1 Owner Service Manual
Yamaha YZ125T1 Parts Catalog
Yamaha YZ 125 2002
Yamaha YZ125 Wikipedia

Btw, I’m available to help over the phone in case u need at

Posted on May 27, 2017


5 Related Answers

Tom Diffin

  • 95 Answers

SOURCE: frount end woddle/weave springer 30 - 40

check the wheel alignment front and rear a little out of alignment and a lot of wobble

Posted on Dec 31, 2008



  • 4 Answers

SOURCE: I,m getting fire and gas its in time hits but wont start

I had a simular problem with my 88 xr. It started out just running bad at higher speeds which had me thinking it was a carb or plug problem. I started changing plugs and had varing results which still had me guessing. So I started adjusting and jetting the carb. Still the same varing results. I suspected the CDI box so I tried to get one. (I live in Thailand, not the easiest thing.) The parts places produced several boxes that plugger in but gave me the results you just described. Good spark but no start, I also got one box that started the bike real good but would not accelerate. There is a built in timing in those CDI boxes. Just thought you might check this, By the way the original box of mine eventually failed completely and I was correct in my suspicions. I found a used one and it runs great.

Posted on Jul 09, 2009


  • 1392 Answers

SOURCE: 1987 yz125 clutch not working!

If you can see the actuator moving, but not disengaging the clutch, it usually means that the clutches are hanging up in the basket, or the actuator is bad and not releasing the clutches. The only way to tell is to take off the clutch cover and watch what happens when you pull the clutch.

Posted on Aug 12, 2009



  • 4565 Answers

SOURCE: bike wont go into gear, just had a new clutch put

With bike not running, rock the bike backwards and forwards and shift through all the gears. If it shifts all the way to fifth gear and back down, then the problem is not in the transmission. If you can't shift the transmission into any gear with the bike not running, just rocking it backwards and forwards, then you've got a problem with the transmission or the shift lever mechanism.

If it does shift but you still can't get it into gear something is strange. I've seen a clutch that the plates were locked together from sitting up, but it still would shift into gear. Of course, when it did shift into first gear, the bike would lurch forward and kill the engine. In this case, we had to disassemble the clutch pack and free the plates up. If you've had a new clutch put in the bike, it could simply need an adjustment. But, usually a new clutch will have a tendency to wear in and start to slip rather than drag. When a clutch causes the bike to lurch when put into gear or become difficult to find neutral with the engine running, it's dragging. I'd check the entire clutch adjustment to start with.

Slide the rubber boot on the clutch cable up, break the lock nut loose and turn the adjuster to make the cable as short as possible. Take the derby cover off the primary to gain access to the clutch release adjuster bolt. Break the large locknut loose, adjust the center bolt inward until you feel resistance. Back the screw back out and back in until you feel resistance again several times. You want to just take the slack out of the adjustment, not start to open the clutch up. Once you've turned the bolt in and feel the resistance, back the bolt back out 1/2 to 1 complete turn. Hold the bolt in this position and lock the lock nut again. Now, adjust the clutch cable back out until you get a freeplay of about an 1/8 inch at the lever. The clutch should be adjusted well enough to release at this point. If it doesn't, the clutch plates are probably stuck.

If the clutch plates are stuck, rock the bike back and forth and shift the bike into fourth or fifth gear. Now, while holding the clutch lever in, push the bike backwards and forwards far enough to "bump" the clutch. This may break the bond between the plates and free it up. If not, you'll have to disassemble the clutch in order to free it up. Good Luck.

Posted on Nov 09, 2009

Testimonial: "Thanks for taking the time to help me out, very informative. Thank you again."



  • 267 Answers

SOURCE: replacing timing chain on ttr 90

There should be a timing mark on the magneto, rotate crank until line is visible thru inspection hole. This will position engine at Top Dead Centre. Have head complete with gaskets, valves, springs and camshft in place and position with camshaft chain in ready position, (you have to hold chain thru camchain opening) Place head on and bolt tight (no need to torque down yet) and pull camchain tight on opposite side to tensioner (fully loosened) and feed over camchain sprocket, take up tension with tensioner screw/bolt. This will have engine TDC with valves closed (as if to fire) rotate engine by hand and ensure tracking of camchain and tension is steady on chain. Valves should actuate in time. Have a close look on camchaim sprocket and a mark of some sort should show against corresponding mark on camshaft journal cuos.

Need the Manual: Down load from the link above, enter model, make year and download for free. (It's in four languages however) The relevent detail is in chapter 4-8 to 4-13. I think, Cheers.

Posted on May 02, 2010

Add Your Answer


Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

My 01 yz125,with a Athena big bore kit- i just rebuilt the top end, took it easy with it for the 2 1/2 hrs i rode it...then i went roll up along side my freind and when i pulled the clutch the bike still...

Raise the back wheel with a stand and see if it starts and wheel spins. With it still on stand kick down thru gears and see if you really are in neutral. Pull in clutch and try to brake back wheel. To me it sounds like a gearbox issue if you really are in neutral (expensive) but could also be a clutch cable (cheap).

May 27, 2017 | Yamaha Motorcycles

1 Answer

Where can I find a big bore kit for a 1985 Honda XR250R

Hi, Anonymous for more information about your question and valuable "FREE" downloads that you will need for viewing and printing please click on the blue links below. Good luck and have a wonderful day.
Piston Kits Al Bakers XRs Only MANUFACTURERS
Motorcycle Big Bore Top End Kits for Honda XR250R eBay
Honda XR250R Service Manual
Honda XR250R Owner Manual

Btw, I’m available to help over the phone in case u need at

May 18, 2012 | 1985 Honda XR 250 R

1 Answer

I have a 2001 yz125 put a new top end in it Blown up in two hours destroying everything Went lean at top end don't know why.

Hi, Rem87012ga how about the specific break in procedures that must be adhered to or using a 16:1 premix ratio in the first tank of fuel for more information about your question and valuable "FREE" downloads that you will need please click on the links below. Good luck and have a nice day.
YZ125 Top End Rebuild
How To 2005 YZ125 Top End Rebuild Pictures Yamaha 2 Stroke
YAMAHA YZ125 Owner Service Manual
OEM parts for Yamaha

Btw, I’m available to help over the phone in case u need at

Apr 30, 2012 | 2003 Yamaha YZ 125

1 Answer

I have a 2004 yz125 with an athena cylinder bored out to a134cc the cylinder keeps filling with coolant I have replaced the head gasket 3 times and the crank seals 2 times What else should I be looking...

Hey , I have just had the same problem on my 2002 yz125 with an athena cylinder , i have sent the cylinder back for a replacement , did you ever fix yours?

Sep 18, 2010 | 2004 Yamaha YZ 125

1 Answer

2006 kawasaki 450f, Athena big bore kit. Coolant is getting into my oil. Replaced both seals, oil and water, and replaced the impeller rod. Runs great, exhaust is normal. Radiator fluid drops...

did u find anything out im having the same problem please help?
did u use the gasket that came with the big bor kit???

2006 kx450 owner

Sep 14, 2010 | 2006 kawasaki KX 450 F

1 Answer

Can i swap my 50cc engine for a 125 or 180 easy enuff to fit in my runner

You can fit a 125 or 180 but you will need grind the engine mounts down - you'll also need to change your wiring loom along with the cdi and ignition unit - your better off putting a big bore kit on your 50 and change the variator and rollers etc - if it's speed your looking for i'd go with the big bore option - if set up correctly your 50 will kick the *** off and 125 - 180

Mar 30, 2010 | 2005 Gilera Runner VX 125

1 Answer

I have a 01 kaw bayou just put a top end kit in now i have piston slap please help even bought a sleeve for it had some yaho pressed @ bored it not sure if he did it right bore diam is 66.8

if it is piston slap,you will need pull the top off again and measure with a feeler gauge between the piston skirt and the sleeve, should only be a couple of thou

Mar 21, 2010 | 2003 kawasaki KX 250

2 Answers

I bought a 2002 yamaha blaster rebuilt top end. New wisco piston and only bored cycl. 20 over. started up second kick. rode great about 3 hrs then parkes it. It ran great. I put 93 gas with yamalube in mix...

Try a new spark plug. Go to a motorsports dealer to purchase a new one as alot of discount or big name store can get a lower grade of sparkplug and this can create alot of grief.

Feb 02, 2010 | 2003 Yamaha TT-R 125 LE

1 Answer

I need an after market cylinder for a cr125r 2004, in australia

Try athena. They make kits, and big bore kits as well. Search on-line for it.

Aug 07, 2009 | 2004 Honda CR 125 R

1 Answer

Using oil after 1/2 top end rebuilt what type oil do u rec.

re- strip top end, hone cylinder bore and then re-assemble piston, rings and cylinder dry, yes that's correct use no oil on piston assy. apart from gudgeon pin. Has the valve stem seals been replaced?

Apr 13, 2009 | 2002 Honda XR 200

Not finding what you are looking for?
2003 Yamaha YZ 125 Logo

Related Topics:

80 people viewed this question

Ask a Question

Usually answered in minutes!

Top Yamaha Experts


Level 3 Expert

3063 Answers


Level 3 Expert

501 Answers

Cindy Wells

Level 3 Expert

6166 Answers

Are you a Yamaha Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides