Fork Alignment

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A poll was taken about 2 years ago, and EVERYONE'S FJR pulled to the left. My 2004 did and my 2007 purchased new does. Shall we take another poll?

Slardy
I don't know who 'everyone' is, but mine sure as hell doesn't pull to the left. It may 'wander' once the tiles are worn and cupped, but it still tracks straight.

Just sayin....

 
Well my smart ass answer would be that maybe your hung like a horse, and should hang your junk on the other side.

But truly.

1) Worn tires - People tend to use different movements and have different levels of comfort with right and left turns, so tires naturally wear different.

2) Steering Head Bearings - Could be a little wear, build up of crud or grease that just caues the head to sit out of position ever so little.

3) I'd remove the front wheel, and support the bike off just one fork and then the other and compare how much compression of the forks you get to ensure you have the same amount of oil, spring tension and preload.

4) I'd test it in a parking lot or an appropriate road where you can go straight down the yellow line. Watch the yellow line. A bike always goes where you're watching, so if you have traffic on one side and a ditch on the other it will go to whatever you are looking at. Of course you could also avoid this by closing your eyes while driving.

5) It's all in your head and now that you brought it up, everybody is out there and thinks that theirs might be pulling one way or another.

Mine tends to pull hard forward, but it's a Gen 1.

 
This thread hasn't been dead for a full year yet, so does it still qualify as a zombie? :unsure:

I recently had a similar experience with the steering pulling on the FJR, except that I knew precisely when it started, which eventually led me back to find the real root cause. In my case, it all started when I serviced the forks earlier this year. I had pulled the forks out and drained the old oil, flushed them out a couple of times with Wally World Dexron II ATF (much cheaper than fork oil) and then refilled them. Upon reassembly, and after adjusting the dampers to compensate for the heavier weight oil I'd used, I was thrilled with the compliance of the suspension, but dismayed that my steering was pulling to the right. Not horribly, but it was definitely noticeable that I needed to keep a small steady pressure on the right side handlebar, and if I took my hands off the bike would veer off line.

I thought, no problem, I just got things skewed when I was doing the triple tree tighten-up dealio. I also have a super-brace fork brace on it, so I also thought that may be involved in the problem.

Even after loosening the axle pinch bolt, fork brace, upper and lower triple tree clamps, and loosening the big steering stem top nut, wiggling things around to find its happy place (can't bounce it in this state) retightened all and, though it was slightly better, it still pulled slightly to the right. :glare:

That's when it occurred to me that the right end of the axle was sitting slightly recessed in the pinch clamp of the bottom of the right fork leg. I couldn't recall for certain whether this had always been the case, or if this was a new development and was part of the steering problem. As it turned out, it was the latter.

I temporarily removed the fork brace and loosened the axle pinch clamp, bounced the bike and then measured the recess of the axle. It was 2mm. I marked the top of the fork's cap with a sharpie for an index / reference point, and then loosened the two right side triple tree clamps and just spun the right upper fork tube 90 degrees in the clamps. Tighten, bounce measure: 3mm. Hmmm, I think we're onto something here. Taking measurements every 90 degrees of rotation I found the "high point" for that fork leg and then aligned that to point rearward. Then I repeated the same thing on the left side leg which was also slightly bent.

After aligning both legs so that the "high points" both point to the rear, re-tightening everything to spec and re-installing the fork brace, the axle still sits ~1mm indented in the right pinch clamp, but the bike now steers as straight as an arrow. Look Ma, no hands again!! :yahoo:

So, the root cause of my steering pull was that the fork legs are both slightly bent. The excursion at the bottom of the fork legs is only just over 1mm p/p on the right leg and just over 2mm p/p on the left one. This is amplified by the length of the leg, which means that actual "bend" is a very tiny angle. This bend may have happened 2 years ago when I smashed into a forest rat that demolished all of my tupperware. I did not detect the slight bent fork legs because they both bent backwards from the impact, which didn't skew the steering. But when I reinstalled the forks after the flushing I did not get them back in the same orientation and this resulted in the steering pull. Ideally forks should be perfectly straight and it wouldn't matter how they are reinstalled, but I wonder how many really are and to what precision?

I'm certainly not going to replace these forks right now as (post alignment) they are working just fine. Now that I know about it, and have the top caps index marked, I can get them back int the same orientation when needed. My thinking in pointing the bend rearward was that 1) this was the direction they would have been in when I popped the bambi, and 2) the bend would be mitigated somewhat by any flexing of the upper fork tubes with the weight of the bike.

So if your steering is pulling on you, try rotating the fork tubes while observing the axle spacing. Your fork tubes may not be perfectly straight either.

 
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I was recently reading Lee Parks, “Total Control” book. He recommends G.M.D Computrack (https://gmd-computrack.com/ ) toaccurately check every aspect of a bike’s chassis alignment. It would definitely be the high tech way tofind out what was wrong. Supposedly theyhave centers across the US. No idea thecost or what they can do to fix a misaligned FJR. It may be worth a call if all else has failed and it a big enough problem.

 
This thread hasn't been dead for a full year yet, so does it still qualify as a zombie? :unsure:

So if your steering is pulling on you, try rotating the fork tubes while observing the axle spacing. Your fork tubes may not be perfectly straight either.
Did the "Fred method" when reassembling my forks after service; there was, indeed, some adjustment needed; it corrected my '08's tendency to veer to the right. :thumbsup:

 
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