So a few months ago I replaced blown fork seal (huge shout-out to Joe for the help and know how!).
When replacing the oil I didn’t look at the bottle I bought and turns out I was shipped 30 weight oil. We didn’t realize it until we had one done.
I haven’t been on anything worse than a few dirt roads since replacing it, on the road it feels fine. My question is, will the compression and rebound be too slow with the thicker oil on bumps and rocks and such off road?
I know it will be a simple drain and fill so not a huge deal, but want to know if I can ride it until springtime. Or if it even needs to be changed.
2005 KLR 650, stock valving, progressive rate springs and what appears to be custom spacers.
On my gen 1 KLR heavier weight fork oil was a purposeful performance upgrade. I would just ride it and see. You can also mix oil weights to suit your needs, like you could remove half and refill with lighter weight to adjust. Not an exact science, but then neither is suspension setup on that set of forks.
FWIW the cogent drop in valve emulators made a huge difference, like I could jump the bike fully loaded very predictably. May not be necessary depending on your riding style.
Smarter people will hopefully chime in regarding potential for damage caused by heavier weight oil.
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Thanks for the Cognent nod, I’m really leaning towards their rebuild able rear shock as well as front valves. Heard nothing but good things.
Guess I’ll have to get it off road and see how I like it and adjust from there.
Yep. I didn’t use their rear shock because it cost as much as the whole bike, but had great results with the progressive 465 rear shock. It was totally sufficient. I have no doubt their shock is amazing, but the drop in valves seemed like a better bang for the buck.
Thanks for that. Much appreciated!
The 2005 KLR has a damper rod fork. The 30wt might be pretty good. I run 20wt to 30wt in my damper rod forks on my vintage race bikes. The low speed damping will be improved with the heavier wt oil, but it might be harsh on wash boards and big hits where the fork won’t be able to react as quickly.
You can also adjust the oil height (larger air gap) to make them feel more plush. This is harder to do by volume only, best to measure the oil ht for accurate results, you need to remove the springs and measure with the fork fully collapsed and vertical. 110-160 mm is typical, the top of the damper rod must always be below the oil level and if you have too small of an air gap you run the risk of damaging/blowing a fork seal.
Modifying the forks with emulators (cartridge valves) from Cogent or Race Tech would be a significant upgrade as they allow speed sensitive damping.
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