Fork Interchangability
- Thread starter deanw
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Exactly that, the spring rates are better suited to how I ride. I've been able to get the suspension to cooperate to my satisfaction with standard damping adjustments on my FJR's. The fact that the 2013 is a bit stiffer front and rear suits me fine. The single fork damping adjuster doesn't bother me. If it's cheaper but still effective, what do I care? And with only one leg handling adjustments, it can be argued that's better too as you don't have to do it twice now. I admit ignorance as to the guts of the fork and grade of materials used. But if the suspension is behaving well (and for me it is), then i don't worry about it too much. I'm not trying to set it up for hot laps at the limit, just good sporting behavior when the road goes curvy.
Spring rates are completely dependent on the weight being carried. Yes, the earlier bikes are woefully undersprung for the average sized American, more so in the forks than the shock. It's a pretty trivial deal to up the spring rate on the forks. I'm pretty sure that the '13 is still undersprung and over damped, but I've not actually ridden one, so I'll have to trust your analysis.
As for the one leg having adjustment, it is simpler. But simpler isn't always better. Having the adjuster in one side means your adjustable range is half of what it is with the adjusters on both sides. It also means that the two legs will be damping at different rates.
It is/was done purely as a means to cut costs. If it was a better way to do it don't you suppose all the race bikes would have single sided adjusters? It may be perfectly adequate for the average rider, but I'm still not sure that it is "better sorted".
As for the one leg having adjustment, it is simpler. But simpler isn't always better. Having the adjuster in one side means your adjustable range is half of what it is with the adjusters on both sides. It also means that the two legs will be damping at different rates.
It is/was done purely as a means to cut costs. If it was a better way to do it don't you suppose all the race bikes would have single sided adjusters? It may be perfectly adequate for the average rider, but I'm still not sure that it is "better sorted".
MCRIDER007
Well-known member
You make some very valid comments about the 13's suspension and why it works for you....and I think that the 13's suspension is probably the best to date, especially the shock that seems to have much better damping on the hard position than the earlier models. However, for those of us that want heavier springs and higher flow damping and have already installed aftermarket suspension, the 13's suspension is not as good as what we have, and it is disappointing that Yamaha chose to save a few bucks on the front forks because that decision will probably cost us much more to work around.
We keep hearing that Yamaha pays attention to its customers' needs and this Forum but the message that the FJR's suspension needs some serious upgrades just doesn't seem to get through. There is a reason the FJR seems to come in last in every magazine shootout and what Yamaha did to the 13 forks was a step backward even though the forks probably are an improvement over the GEN2 forks.
I like the other changes Yamaha made to the FJR and if the 13 had an inverted fork I would have one in my garage. I probably would have bought one without an inverted fork if they hadn't screwed up the left fork since I have a set of Traxxion AK-20s ready to install, but I want fully adjustable suspension on both forks so I am just going to have get by with what I already have.
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Apparently R1's and M1's have asymmetrical fork damping and probably not for cost reasons. I'm not suggesting in the FJR's case that it wasn't to cut costs, just that it doesn't necessarily mean it's cheap or sub standard.
From the R1 "features" section on Y's site:
Suspension includes YHSJ (Yamaha Hydraulic Systems Japan) front forks which use one of the tricks developed for our winning MotoGP® bikes: independent damping. The left fork handles compression damping and the right side handles the rebound damping.
The YZR-M1 is supposed to have fully adjustable Ohlins forks. I'm not sure that the functions are actually split on that.
The YZF-R1 claims they were inspired by a trick from MotoGP racing by splitting the functions. There may be some advantage (not sure what), but the R1 is also just a production sport bike, not a race bike, so the cost of components is a real factor on the R1.
The odd thing about the FJR design is that one leg has both damping adjustments in it. Not sure what possible advantage there could be to doing that other than cost.
The YZF-R1 claims they were inspired by a trick from MotoGP racing by splitting the functions. There may be some advantage (not sure what), but the R1 is also just a production sport bike, not a race bike, so the cost of components is a real factor on the R1.
The odd thing about the FJR design is that one leg has both damping adjustments in it. Not sure what possible advantage there could be to doing that other than cost.
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MCRIDER007
Well-known member
I was told by a tech at GP Suspension that the splitting of the functions is to make it easier to set the suspension for a specific track. He said the racing team will have 20 sets of forks, all set up slightly different and they will swap forks rather than making adjustments. I'm not sure why this is more efficient although it may take the constantly changing fork oil temperature and viscosity out of the evaluation.
The term rebound damping in one side and compression damping in the other may be misleading, I think they are actually referring to the ability to adjust only one of the damping functions per fork even though the fork has both rebound and compression damping (this is speculation at this point, I have not had the opportunity to examine the damping components on a split function fork).
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