[sx3shooter]

Hi all I am new to the forumn. I found it while searching for atv answers. My foreman started to make a funny noise while camping over the weekend. When I put it into gear whether forward or reverse it makes a chirping or high pitched tinking sound. It does it again as a load is applied to the motor after as the torque starts turning the tires the noise doesn't contiue until I stop and either start again or shift from neutral to first gear or reverse. I honestly thought it was an exhaust leak that was whistling. However after closer examination I have determing the noise to be coming from the rear end. I had to have honda rebuild the differential in 08. The pinion nut had come loose and I didn't have time to even attempt to fix it. I am almost wondering if it's the pinion joint that connects to the rear drive shaft or the ringgear clanking against the rear axle. Thanks in advance for any help or pointers.

 

[450RMAN]

Yea Sounds like a bearing or a CV joint, do you have a strait axel or a independant susp.

 

[Helmut]

Yea Sounds like a bearing or a CV joint, do you have a strait axel or a independant susp.

The 450 Foreman has a straight axle. Yeah, it sounds like a u-joint or cv joint.

 

[sx3shooter]

I can't find a schematic of the rear drivetrain that shows a u-joint of cv joint but I swear there has to be something that allows the swingarm to move and the drive shaft to move with the swing arm.

 

[Helmut]

I can't find a schematic of the rear drivetrain that shows a u-joint of cv joint but I swear there has to be something that allows the swingarm to move and the drive shaft to move with the swing arm.

The u-joint is inside the rubber boot in the picture below.

 

[Helmut]

If it's not the u-joint, it might be in the differential, itself. Have you checked the gear oil in the differential? When you check it, look for any signs of metal chips or filings in the gear oil. Also, check your axle bearings for any movement, it could be bad bearings. If it's not the bearings or u-joint, and you're positive the noise is coming from the rear end, then all that's left to do is to take the rear end apart and visually look for any damaged or worn parts. Also, check the splines on your driveshaft and pinion shaft.

 

[sx3shooter]

Thanks "Helmut" sadly I won't have a chance to get into the thing till thursday. I promise to keep you all posted.

 

[Helmut]

Thanks "Helmut" sadly I won't have a chance to get into the thing till thursday. I promise to keep you all posted.

You're welcome. Good luck with it, hope you get it fixed.

 

[sx3shooter]

ok can I pull the shock bolts and the swingarm bolts and pull the swing arm that way? I know I would have to lose the breather lines and the brake lines. Or do I really have to pull the whole thing apart from the axletubes forward? I first want to check the u joint and the swingarm bearings. Also I noticed on the left side between the swing arm and frame that the gap is tighter at the top than at the bottom. The gap on the right side is even all the way around. Could my noise be swing arm bearings or a bent pivot bolt? I know that the bolt on one side it only torqued to 2.9 ft lbs and the other side is 87 ft lbs. I haven't tore into the wheeler yet because my buddy is going to machine me a lock nut wrench for it. Honda quoted me 100 bucks for the stupid wrench.

 

[Helmut]

ok can I pull the shock bolts and the swingarm bolts and pull the swing arm that way?

Yes, you can remove the whole swingarm like that. You don't have to remove the axle or axle tubes, first. Before you do that, though, try removing one of the clamps on the rubber boot and slide it back and see if you can see the u-joint and tell if it's bad before you pull the swingarm.

I doubt that the swingarm bearings are making that noise, but I could be wrong. They might be bad, though. Usually, you can get a hold of the back racks and wiggle the ATV from side to side while looking at the area of the swingarm bearings to tell if they're bad.

 

[sx3shooter]

Thanks Helmut. I tried moving the boot both directions today to look at the u joint I couldn't get it to move enough to really see or do much maybe there is a trick to it. I have shook and bounced the rearend and I really didn't think it was the swing arm pivot bolts but figured I would ask anyway.

 

[sx3shooter]

Well between the constant rain and my 12 hr work schedule I have not had the chance to tear into my foreman. I did pull the boot back to reveal the U joint and couldn't hear the noise coming from there. It seemed to be coming from farther back. However I also did notice moisture has gotten into the u-joint area so when I tear it down I will be looking for bad seals as well. My tool should be finished for the swingarm lock nut tomorrow. One other question I once tried to get the rear brake drum off and couldn't do it. I took the cover off and unhooked the brake cables what else am I missing? I am assuming its not much different than an automotive brake drum.

 

[Helmut]

One other question I once tried to get the rear brake drum off and couldn't do it. I took the cover off and unhooked the brake cables what else am I missing? I am assuming its not much different than an automotive brake drum.

Try taking a hammer and tapping around the side of the brake drum. Sometimes that will jar it and it will come off. If that don't work, try moving the lever on the back, back and forth, while trying to pull the drum off.

 

[sx3shooter]

Ok so I finaly got to tear into the foreman. Rear drive shaft was rusty and so was the u-joint. The u-joint did seem to have some play in it. Also found the source of the water leak the u-joint boot had a small hole in it. I then tore the whole swingarm apart to see how much water damage I had. It was all contained in the drive shaft area. So off to the dealer tomorrow to order parts. All the bearings and dust seals seemed to be in good shape.