r6 shock swap why is ride height greater?

[geezer]

I swapped the stock shock for the r6 with the fzr spring. I used the adjustable dog bones set to 138mm center to center. My rear ride height increased by 40mm. It seems that the bike should have been about original height with r6 shock and 138mm bones.

I measured the orig ride height from same points before and after. I measured twice and recorded the number before swapping. The bike had the original dog bones although are stamped 1wg like the fzr400? but are the stock length I think 147 mm center to center.

I cant get back to my original height even with the dog bones out to 150 mm.

It handles good right now about 15 mm higher than it was when I started. Should I not trip about that initial measurement? It just boggles my worn mind why.

Looks like the stock swingarm. The relay arm looks like the stock one but Im thinking it cant be what else could change this?

What gives????

[rotortech]

According to the fiche at one of the distributors the Yamaha part number for the stock bones is 1WG-2217M-00-00. So your part with the 1WG number is probably the correct stock part. So which number do we believe now? The original ride height number that you took or the ride height after the R6 installation. I wonder if the original was modified in some way that you were not aware of.

[fzrbrandon]

What year R6 is the shock from? It's possible that different years are of slightly different length (I'd actually be surprised if this WASN'T the case). I have an '06 / '07 on my 600 with 138mm bones. The ride height is REAL close to what it was before the swap. I haven't measured it to get the exact difference (if any) but my reach to the ground is about the same. Believe me, I, of all people, would notice a 40mm increase in ride height.

BTW, the stock bones (stamped 1WG - same part as on the 1WG 400) are 148mm to the best of my recollection.

[dru86]

it's probably because you've put the fzr spring on the r6 shock. The fzr spring is a fair amount longer than the r6 spring, when the fzr spring gets put on the r6 shock it is compressed far more than when it was on the fzr shock. Basically the fzr spring is the right rate spring but is too long for the r6 shock. Have you backed the preload collar off as far as it goes? Did you do topped out measurements of the rear end before and after the shock install?

[rotortech]

it's probably because you've put the fzr spring on the r6 shock. The fzr spring is a fair amount longer than the r6 spring,

Dru - you are probably correct in this case. That was not the case when I swapped the springs. So there may be different length R6 shocks or at least R6 shocks with different length springs. I really don't know.

[reelrazor]

Dru - you are probably correct in this case. That was not the case when I swapped the springs. So there may be different length R6 shocks or at least R6 shocks with different length springs. I really don't know.

No, there aren't.

The shocks have pressurized nitrogen bladders, spring or no spring, they maintain their longest length UNLESS loaded. Remove the spring and compress the shock and it will return to fully extended-the same length as if it had a spring mounted. Changing spring rates OR lengths will have nothing to do with the shock's eye to eye length.

This case of geezer's is baffling to me.

Was the pre-swap height checked with the rear end unloaded? How about the post swap measurement..unloaded?

Or, are we talking about static sag measurement? If so, this could be where the discrepancy lies..

I dunno

[dru86]

What I'm talking about is the sag measurements. Putting a longer spring on there WILL change how much sag the bike has and this WILL effect how high the bike sits. The fzr600 spring puts an enormous amount of preload on the r6 shock. Correct free sag is about 10mm (bike weight only) and ~30mm rider sag. When I put the fzr600 spring on my r6 shock(06) it basically had no free sag and about 10mm rider sag. Read all about suspension here Peter Verdone

[yamaha_george]

Dru,
I actually found this link http://www.peterverdonedesigns.com/suspension.htm better for all round tuning of suspension by the same guy

[geezer]

Thanks for all the possible reasons. The shock was from an 09. I did not do a static sag check before I replaced the shock. I did take before and after measurements unloaded [cant remember if i was loaded].

The fzr spring was definitely longer than the r6 spring. Kind of tuff to put on those spring compressors were twisting and moaning. I would assume there are different lengths on the r6 or fzr srpring since people have seen both the same lengths and differing.

I would think that RR is right as far as that shock only getting so long no matter what spring used.

I havent checked static sag yet but rider sag is about 30 mm with preload on lightest setting.

ok so I did check the rake and that is pretty close to factory 25 degrees now that I have gone back to the 138 mm dog bone length
When bones are ran out to about 150mm rake is around 26 degrees

I stopped tripping and went skipping today and did a real test. I headed for the hills and gave it a real world test. Handled great except for my frozen bones being a little to stiff for super hard riding. Thanks for all the help.