Front Fork Tubes - Motorcycle-Journal Forums

Ranger_b0b · 10-03-2005, 12:38 PM

Ok, So I was replacing my fork seals this weekend, and the forks were very difficult to get out of the tree. I didn't really think anything of it, cuz the bike is 23 years old, and its probably the first time the tubes have been pulled. Well, turns out that the upper tubes are slightly bent, not enough to cause the forks to bind, but enough that the tube does not line up with the upper clamp of the triple tree when both forks are on the bike. My questions are:

1) It is normal to have some "bow" in the upper tubes? The runout is probably only .0625"

2) If not normal, is this OK? Do I just need to screw with the forks until I get the bow the right way? I looked in the Factory Service manual, and didn't see a spec for this.

As a side note, this probably explains why the bike pulled to the left with no steeering input from me. Thanks in advance for any info.

Ranger_b0b · 10-04-2005, 07:52 AM

Ummm....Anybody?

bat4255 · 10-07-2005, 08:09 AM

The only experiance I had with bent forks, was 30 + years ago. Riding dirt bikes, and falling off of gravel pit walls, and general beating the crap out of the bike. I did have to straighten the forks a few times with a press, but the bike still did work fine. My dirt bike worked at .250 off, not the best, but it did function. You may have some very minor handling issues. Unless you are on the track, and riding to the limit, I don't think that (.0625) amount is anything to worry about. You can take the forks to an automotive shop (full service) or a machine shop, to try and straighten it. This might help you alignment problem.

Sometimes all that happens is the triple tree clamps loosen up. I used put the front wheel next to a tree, or large rock. Then crank on the handle bars, to straighten up the front wheel, relative to the handlebars, the tighten it up.

Ranger_b0b · 10-07-2005, 06:12 PM

Thanks for the reply bat. I actually got this problem figured out now. the forks were bent less than I thought (max 0.035") but upon further inpection of the front end, the steering tube is bent! :

: So, this weekend, its back to the shop, and try to straighten the tube, which I think will be pretty easy to do with a torch set

bat4255 · 10-08-2005, 09:14 AM

Glad you found the cause of the handeling problem. It could be tricky to fix, but good luck.

10-03-2005, 12:38 PM	#1 (permalink)
Ranger_b0b Clunked into first gear Joined: Jul 2005 Bike: '82 Suzuki GS650L Location: Sparta, MI (-85.69978/43.16359) Posts: 221	Front Fork Tubes Ok, So I was replacing my fork seals this weekend, and the forks were very difficult to get out of the tree. I didn't really think anything of it, cuz the bike is 23 years old, and its probably the first time the tubes have been pulled. Well, turns out that the upper tubes are slightly bent, not enough to cause the forks to bind, but enough that the tube does not line up with the upper clamp of the triple tree when both forks are on the bike. My questions are: 1) It is normal to have some "bow" in the upper tubes? The runout is probably only .0625" 2) If not normal, is this OK? Do I just need to screw with the forks until I get the bow the right way? I looked in the Factory Service manual, and didn't see a spec for this. As a side note, this probably explains why the bike pulled to the left with no steeering input from me. Thanks in advance for any info. __________________ Mike aka IronHorse of Hell's Beergut MC He that is good for making excuses is seldom good for anything else. - Benjamin Franklin '82 GS650L - Rescued July 05 - Resuscitated Aug 05 www.myspace.com/mike_hiler

10-04-2005, 07:52 AM	#2 (permalink)
Ranger_b0b Clunked into first gear Joined: Jul 2005 Bike: '82 Suzuki GS650L Location: Sparta, MI (-85.69978/43.16359) Posts: 221	Ummm....Anybody? __________________ Mike aka IronHorse of Hell's Beergut MC He that is good for making excuses is seldom good for anything else. - Benjamin Franklin '82 GS650L - Rescued July 05 - Resuscitated Aug 05 www.myspace.com/mike_hiler

10-07-2005, 08:09 AM	#3 (permalink)
bat4255 Squirrel Target Joined: Dec 2003 Bike: Burgman 650 K3- 29,100 miles as of 10-20-08 Location: Dodge Co. Wisconsin Posts: 663	The only experiance I had with bent forks, was 30 + years ago. Riding dirt bikes, and falling off of gravel pit walls, and general beating the crap out of the bike. I did have to straighten the forks a few times with a press, but the bike still did work fine. My dirt bike worked at .250 off, not the best, but it did function. You may have some very minor handling issues. Unless you are on the track, and riding to the limit, I don't think that (.0625) amount is anything to worry about. You can take the forks to an automotive shop (full service) or a machine shop, to try and straighten it. This might help you alignment problem. Sometimes all that happens is the triple tree clamps loosen up. I used put the front wheel next to a tree, or large rock. Then crank on the handle bars, to straighten up the front wheel, relative to the handlebars, the tighten it up. Last edited by bat4255; 10-07-2005 at 08:17 AM.

10-07-2005, 06:12 PM	#4 (permalink)
Ranger_b0b Clunked into first gear Joined: Jul 2005 Bike: '82 Suzuki GS650L Location: Sparta, MI (-85.69978/43.16359) Posts: 221	Thanks for the reply bat. I actually got this problem figured out now. the forks were bent less than I thought (max 0.035") but upon further inpection of the front end, the steering tube is bent! :: So, this weekend, its back to the shop, and try to straighten the tube, which I think will be pretty easy to do with a torch set __________________ Mike aka IronHorse of Hell's Beergut MC He that is good for making excuses is seldom good for anything else. - Benjamin Franklin '82 GS650L - Rescued July 05 - Resuscitated Aug 05 www.myspace.com/mike_hiler

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10-08-2005, 09:14 AM	#5 (permalink)
bat4255 Squirrel Target Joined: Dec 2003 Bike: Burgman 650 K3- 29,100 miles as of 10-20-08 Location: Dodge Co. Wisconsin Posts: 663	Glad you found the cause of the handeling problem. It could be tricky to fix, but good luck.

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