Frontforks

I did not see any topic regarding the frontforks as in how comfy they are.
I still can not comprehend as in why the FF are so hard on small bumbs and small potholes but on other occasions do a tremendeous job on harsh pavement.
The frontwheel is heavy (15-17 kg with discs and tire) in regard to other bikes I owned. Even my mechanic complains about it.
The tires I'm using now are the lightest I've had and can feel the difference quit well.
The weight is about 2 kg less (tubeless now) is definitly better in tire-roadcontact than the previous tires (Bridgestone BT45 with or without innertube).
The progressive spring do their job very well but those short bumbs are still a pain in the uhh, not comfy I mean. Antidive is ok (minor antidive). I shut down the airpressure possibillities because have no need for that. Fork oil is 5w30 synthetic. Tried other oils and viscosities, and airchambervolumes, but I like this multigrade motoroil the best.
Suitable for all temperatures (-5 to +40 C.) Monogrades harsh up when cold and/or get to thin when hot.
I'm quit happy now but for the small bumbreaktions.

 

Have you rebuilt the forks?

 

Nope.. not as in completely but the innerworks i've seen and checked.
I believe its inherent to the bike or forks (angle) and can be tweaked but only in a minor manner.

 

One thing to keep in mind is that there is no adjustable compression damping (other that that from the anti-dive unit). The adjustable air spring is necessary, as it is the precursor to adjustable compression damping and nitrogen filled forks. I suspect that is why you're having an issue with small/sudden bumps and potholes.

Refit the air system and use it. Otherwise you'll have to look at a front-end swap from a newer Yamaha that has adjustable compression damping.

 

Thanks for the add. info but what's about your remark about nitrogen filled forks?
I can't recall i've anything read about that, tires ok but forks?
Maybe all is fine with the forks and is it me who is to sensitive..

 

I would use the correct fork oil for the bike, the oil is developed to cope with the various amounts of stress involved, engine oil is engine oil for a reason. I tried using engine oil in my XJR forks and soon swapped back.
Have you tried some progressive springs too? Just because it's a rat bike you ride doesn't mean it doesn't need help in the handling department.

 

I did and it didn't go well as I mentioned due to the range of temp. I'm riding in.
The bike handles very well in corners and highspeed (corners). No shimmying, wobbling, weaving or whatever. Just the small sharp bumbs or those 'sleeping cops'.
With the lighter tire it improved noticeably so just guess the weight of the frontwheel is the culprit and can't change that.
Tried to change that with a spokewheel but the price was to steep to manufacture. Guess I just have to, and will, live with this feature.
In the topic Secarat you can read what is done to the bike.

 

Just rebuilt forks on my Johnny Cash bike , filled with 20 w fork oil which is fine for me anyway.

 

On (semi)smooth tarmac there is no problem at all but we do still have some cobblestone roads here. Those aren't flat surfaces.
I contacted some other folks, with (more) modern bikes, and most of them agree that with progressive springs the comfort on low speeds is less.

 

On mine, there's no air assist, apart from the air trapped in the top of the fork legs (which does contribute to the suspension).
I took them apart shortly after getting them because one leg had the habit of pumping up, which caused a very odd handling indeed.
On rebuilding them with new seals (nothing amiss found within) I used the recommended amount of oil, but just used what I had to hand, which was a 5w40 synthetic engine oil.
Amazingly, I didn't crash and burn, nor did my hair fall out. In fact, it handled nicely and predictably and I'm pleased to note the odd leg pump-up hasn't occurred since. If it re-occurrs I'll link the two legs with air caps, but so far, so good.

 

Seems you have found out too that motoroil can do the trick well and it's cheap also. I've been experimenting with the airchamber/oilamount aswell.
The SecaRat has 25 cm of air with the springs inside = 230 ml/leg.