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DMMEYER

2001 wr426 5th gear spiking

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I have a 2001 wr426 that spikes and what I mean by spiking is that as soon as I shift into 5th gear and 5th gear only the bike jerks me back and forth. I have had the bike in for a tune up at a local race shop (Langston's Racing in S.Cal) they checked the cams, jetting, timing, new spark plug but it didn't help. When I went to pick up the bike I took it for a test drive before I left to see if they fixed it. They didn't. They put it back in the DINO room and showed me that the jetting was perfect but the bike still jerked in 5th gear and the gauge that was connected to the ignition coil was spiking from 6k to 10k rpms. The mechanic kept it for a couple more days and said that it must be electrical because everything he check was fine. So I started changing parts, I first change out the TSP, but that wasn't it . Then I change the ignition coil, no that's not it either. Next I change the CDI, strike 3. I took all these parts off of my brothers 2001 wr426 that runs just fine. I talked to a couple of friends and they think it's the carburetor. Should I take the carb. of my brothers?????? If that one works then what should I do to my carb. I haven't taken this new of a carb. apart. By the looks of the diagram in my manual theirs allot of parts to this carb. I wouldn't know what to look for.

The bike runs just fine in 1st through 4th.

Can anyone give me some assistance on this. I would really appreciate it.

DEE

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Try your gearbox!

It sounds like a rebuild to me. My '01 yz250 did what you say which was popping out of 5th gear. Not electrical at all.

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No. Teeth break off cogs and syncro's shit themselves.

This is what my problem was. 1st - 4th was fine just 5th would pop in and out of gear.

I had to send mine away to get fixed.

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Sorry to bring bad news, but the dogs have broken off 3rd gear (which drives 5th gear) I know the feeling you are describing because my 01 426 did the same. Suprised your shop didnt figure this out :)

It'll look something like this:

gearbox.jpg

a few new gears and at least one new shift fork and you'll be ready to go again.

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me too mine is in hospital with gearbox injuries - syptoms exactly like yours.

I would say the dogs which engage the gears are all worn - common on '01's.

Shift forks may be damged due to worn gears, teeth on face of gears likely worn too.....stop riding it will get worse.

To make you feel a little better bits of gears somehow found their way right through my motor, wrote off the rotor and spread more metal crap through everything - full rebuild - parts list looks like a manual.

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It cost me $1100 but I am in Australia and I got a full engine rebuild with some porting done.

I wouldn't do it yourself, it is a big job. Take it to someone else who knows what they are doing. I wouldn't pay the bloke you took your bike to as they are ripping you off and know @#$% all (like me!).

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Add another to the 5th gear skipping club. :) It just feels like the engine has a miss, but get progressively worse.

Anyone know if any of the OEM parts have been updated over the years for better durability?

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Well today I split the case and 5 hours later eveything looks brand new. Gears look good, shift forks have very minor wear on them. Now what should I do, did I miss something? :D:D

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I had something similar in my 04 WR450F but I did not notice if it was only 5th gear.

When it had to pull hard (Torque) it would spike similar to what you are describing.

I turned of the lights and then it was OK

Later I exchanged the original battery and have not had this problem again.

It may not be the same but worth the post, I hope.

Put a new battery in and try it, put a voltage meter on it where you can see it while driving.

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No battery. I was going to hook the bike up with a Baja Design kit but figured I take care of this problem first.

I ran the bike in 5th gear with the lights on and off and it didn't make a difference - still spikes.

Does anyone have any idea what's wrong with my bike

. :D:D:D:eek::eek::eek::D:D:D:p:D:eek:

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I take back my prior message about all the gears looking new and the shift forks having little wearing. I brought the case to 74 motorsports in cali and the parts manager helped me take the axles out and to my surprise YOU GUYS WERE RIGHT :D (I was looking at them while they were still going thru the case) :eek::D The 2nd shift fork has a grove in it about 1/32 deep in the side were the gear was grinding into it and the 3rd and 5th gear cog heads were rounded So that's why my 5th gear was spiking, the cog heads were slipping in and out on the inside of the gear. This is also why I couldn't see any wearing on the gears, they were hiding in the shadows.

Well with all this new discovery and the help of the cool people at 74 motorsports, I ordered all the needed gears, gaskets and seals today so hopefully I can get it back together this weekend.

Thanks allot guys for your assistants I real appreciate the help. :eek::D

Sorry if it sounded like I didn't believe you guys, I just didn't take the last step.

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I had the same problem... same solutions!!!

New model, still have this problem??? Or only 2001 an older???

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I had the same problem... same solutions!!!

New model, still have this problem??? Or only 2001 an older???

New model does it to .Blown 5 gear today 04 WR450F 5000 KM. More :thumbsup: money.

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has the aftermarket addressed this problem yet? I thought I felt mine pop 2 or 3 times last ride so I'm expecting to be in the same boat... I would like to replace the parts with something permenent... oem just sounds to me like a temporary fix...:thumbsup:

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has the aftermarket addressed this problem yet? I thought I felt mine pop 2 or 3 times last ride so I'm expecting to be in the same boat... I would like to replace the parts with something permenent... oem just sounds to me like a temporary fix...:thumbsup:

Some people are getting the gears 3rd and 5th back cut. It seems to fix it .I will be getting my gears done see what happens .

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