05 crf450 chain issue

[xderminator]

I have a 2005 crf450 with low hours. I'm the second owner. when i got the bike i noticed that under acceleration the chain would snap from side to side hitting the tire and rear shock mud flap. The OEM chain and sprockets were clapped so i replaced them. the problem still exists. I figured the countershaft bearing was shot. I split the cases and it's in perfect shape.( i had already checked the rear wheel bearings,hub etc. and everything is ok and straight) Any body heard of this ? thx

 

[SpeedyManiac]

Do you have the rear wheel aligned correctly? How are the rear wheel bearings?

 

[xderminator]

the bearings seem ok and the 05 crf uses identical wheel spacers on either side. I'm going to replace the bearings when i do the motor rebuild. perhaps they have been replaced abd weren't seated correctly. I doubt it because the bike had approx. 20-30 hours on itat most when i bought it. thx

 

[holeshot]

The rear mud flap on my CRF is constantly being chewed by the chain. It's always been like this - doesn't worry me.

 

[xderminator]

it's the fact that it turns a new tire into an old one after one ride that bothers me a bit.

 

[nicbullseye]

???

you do have an o ring chain?

 

[bwood]

See if you can wiggle the countershaft (front sprocket) front to back. This may cause the chain to be misaligned with the rear sprocket no matter what the rear marks show. The only fix for this is to replace the bearing behind the countershaft (splitting cases). This would be VERY rare and more than likely would be caused by improper chain tension (too tight). If you are using an o-ring chain, you may need to purchase a front sprocket spacer to compensate for the increased width of the chain. Check out Fastway for this spacer. Also make sure you are adjusting you chain properly. The bike should be off the ground with the swingarm fully extended. Check you chainslack at the end of the swingarm chainguide/protector. I think on the CRF450R it should be around 1 1/4" or 32mm (Honda says 1 1/5 or 30mm which would be just under 1 1/4", but the 1/4 is easier to read). When you are done adjusting your chain, the rear wheel should freewheel with an oiled chain. You might even spread the rear caliper apart to take its friction out of the equation. When you are tightening the axle nut, make sure to push wrech foward against the adjuster and not pull the wrench back or up as this will pull one side back some.

 

[whenfoxforks-ruled]

Front sprocket rocking too far, swingarm or wheel bearings. Disconnect the rear shock and bring the wheel up far eough to see if the chain is straight. If it is from running an o ring chain against the tire, I would sure put a standard chain on.

 

[Spokes574]

Chain grinding mud flap - frame noise

I have an Y05 crf450R and had a chain issue. When the chain slaps around it tends to make noise up front via vibrations through the frame and I thought I had an engine issue. Rich on this forum explained to me that that noise is probably a chain issue. Sure enough, I checked the mud flap and it was really chewed up. So I tighten the chain to a snug 3 fingers. The noise up front went a way and now the mud flap gets a tad bit of chewing. Mud flap on crf450R do get a little bit chewed regardless. So I would suggest snugging the chain to a 3 finger snug. Also check the front sprocket bearing. I will guess you are running the chain too lose. You will have to run it more tighter than your other bikes.

SPokes574

 

[Polish_Mikeski]

Make sure your rear tire is in good alignment, also make sure your chain is within the service limit for free play before you have to adjust it when I go to the track and ride for about 2hours its time for me to make adjustments to the chain, cause it just stretches like crazy.

 

[whenfoxforks-ruled]

2 hours! Oem chain? 20 minutes and check the free play. Replace with the gold chains, it is well worth it.