Rocking the forks

[po18guy]

OK, here's one for the Guzzilluminati: Bike came with forks slightly askew. Dinged bar end tells me a garage tip over. Some say to loosen everything beneath the upper triple and rock the forks back into alignment, check for square and tighten. But, this was for curb impacts, where the force came form the wheel. What if the twisting came from the bars?

[Scud]

I'd loosen everything, get it about where it looks good. Then snug-up the top triple. To help put everything in alignment, you can spin the front wheel while the lower triple is loose, then hit the brakes hard. The sudden stop of centrifugal force will snap things into pretty good alignment - better then you can do by eye-balling it. Then you can go around and torque down everything (including the top triple).

[po18guy]

Leave the lower triple tight then?

[Scud]

If you're really concerned about the alignment, remove the front wheel and loosen everything. That also gives you a chance to raise the forks a bit if you want to. FYI -Most of my experience with misaligned forks is with dirt bikes. Somebody with more experience with setting up street suspension may be along soon.

[Lucky Phil]

4 hours ago, po18guy said:

Leave the lower triple tight then?

Take the weight off the front with a jack under the engine and loosen off all the triple clamp bolts including the stem clamp bolt, wheel clamp bolts, front guard bolts, brake calliper bolts and axle then grab the wheel between your legs and jiggle the bars from side to side to release any tension and tighten up the triple clamp bolts then the stem clamp bolt then the axle nut drop the weight back onto the front wheel pump the forks up and down with your weight and then tighten up the axle clamp bolts the calliper mount bolts and the front guard mount bolts.

Ciao   

[po18guy]

Thank you. Sounds like a plan. Yet another use for the centerstand. I have developed a technique for hoisting the lump up there without sending my back into spasms.

[Chris Wilson]

Also obtain a plank of wood longer than the bike, cut in two recesses out it on the same side half the width of each tyre.

Place plank along both the tyre edges, making sure that both tyres are vertical and matching each recess to it's appropriate tyre width. This will shown the aligment of the tyres as a final check and is the end goal for any of this.

Chris.

 

 

[Lucky Phil]

30 minutes ago, Chris Wilson said:

Also obtain a plank of wood longer than the bike, cut in two recesses out it on the same side half the width of each tyre.

Place plank along both the tyre edges, making sure that both tyres are vertical and matching each recess to it's appropriate tyre width. This will shown the aligment of the tyres as a final check and is the end goal for any of this.

Chris.

 

 

So whats the plan when you find it's out of alignment?

Ciao

[Chris Wilson]

Since most bikes have a chain final drive with a double arm swingarm and left and right vernier adjustments you can accommodate slight out of alignment with this.

Failing that, and assuming all the sage advice about loosening the attachment points on the forks and resetting them is followed, you have something bent that a simple adjustment won't fix.

If the frame is bent then remove front steering spindle and swing arm pivot, place in rods with tapered cones to centre and check perpendicularly.

Install front suspension and do the same check using swing arm pivot and front axle journals and then install rear suspension and use front axle and rear axle journals.

Check wheels for warps, install and finally check with alignment board again

Why do you ask?

 

Chris.

[Lucky Phil]

45 minutes ago, Chris Wilson said:

Since most bikes have a chain final drive with a double arm swingarm and left and right vernier adjustments you can accommodate slight out of alignment with this.

Failing that, and assuming all the sage advice about loosening the attachment points on the forks and resetting them is followed, you have something bent that a simple adjustment won't fix.

If the frame is bent then remove front steering spindle and swing arm pivot, place in rods with tapered cones to centre and check perpendicularly.

Install front suspension and do the same check using swing arm pivot and front axle journals and then install rear suspension and use front axle and rear axle journals.

Check wheels for warps, install and finally check with alignment board again

Why do you ask?

 

Chris.

Because on an uncrashed shaft drive bike there's nothing you can do about it except live with it unless you want to strip it down and take it to a frame aligner. Which then beggars the question, how much misalignment can you live with or find acceptable? If you know a shaft drive bike hasn't been down the road in a serious way some things are better not to know.

Ciao 

[docc]

So, on our V11 we can change the lateral position of the swingarm in the side supports. After replacing my swingarm from crash damage in 2003, I went to great pains using a laser to align the contact patches. Later, we had some fun at a South'n Spine raid measuring the swingarm offset amongst several V11 present (they were all over the place). My personal experience has evolved to make both of the support pins symmetrical.

Yet, I am just making the point that the swingarm can be shifted a bit side-to-side in the event one felt the need to alter the alignment.

[Scud]

1 minute ago, docc said:

My personal experience has evolved to make both of the support pins symmetrical.

Yet, I am just making the point that the swingarm can be shifted a bit side-to-side in the event one felt the need to alter the alignment.

I'm with you on this Docc. Simply adjust those support pins to center the swingarm between the frame plates, which also ensures maximum clearance for it to pivot (and never bind or rub). That is mechanically satisfying, and I don't think I'm a good enough rider to tell if my wheels are a few mm off alignment.

[docc]

IIRC, when @danl checked my swingarm offset, it was 0.028" (less than a millimeter). I put that down to error in my laser alignment method and decided to simply center it. The Workshop Manual only says to put it back where you found it. Our discussion at the South'n Spine Raid led to the consensus that an enthusiastic V11 owner is more likely to take the care and time to set this precisely compared to Luigi-on-the-Line.

[Lucky Phil]

3 hours ago, docc said:

So, on our V11 we can change the lateral position of the swingarm in the side supports. After replacing my swingarm from crash damage in 2003, I went to great pains using a laser to align the contact patches. Later, we had some fun at a South'n Spine raid measuring the swingarm offset amongst several V11 present (they were all over the place). My personal experience has evolved to make both of the support pins symmetrical.

Yet, I am just making the point that the swingarm can be shifted a bit side-to-side in the event one felt the need to alter the alignment.

All true docc but what's the level of maximum misalignment from the pins? a few mm at most. Reading about the the prototype Magni Australia Guzzi's that ran 30mm offset to clear the drive shaft. They later built an aluminium swingarm to get it back to 15mm. My point here is you wont feel or notice a few mm anyway and if your V11 is miles out was it that way from the factory. Some bikes come from the factory with misalignment. I spoke to a a racer that raced a CBR600 Honda back in the late 90's and they came from the factory with 20mm misalignment std. They were all the same. He was an ex factory Honda rider BTW. 

Did you measure your bikes alignment as dead true with a lazer aligner? I'd be amazed if you lazer aligned 10 new Guzzi V11's and found 1 that was dead true. Both my BMW K100RS's from the mid 80's were misaligned from the factory. Nothing you could do about it.

Ciao   

[Chris Wilson]

With any mono mounted wheel shimming or skimming would allow the hub or the mounts adjustment.

Personally, I would want to know if my bike had errors built in and would endeavour to correct them.

On my Bellagio with spoked wheels it's simply a matter of tensioning the spokes to include offset 'if' it needs it .

Chris.