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i’m restoring my first Triumph, I have a 76 Bonneville any recommendations on the type of fork oil I should be using ?
Thanks Don I appreciate your insight I’ve already contacted LP Williams. I’ve bought and aftermarket seals and O-rings and already installed them. The forks are still dry I think I’m going to make the switch to the LP Williams. ThanksHi 76barnfind, Book calls for ATF. I’ve used ATF F & ATF Decron II & III, Mercedes 134A.
To me they feel the same.
I find ATF is very close to 7 to 7.5w Belray fork oil. A change of only 2w can be decidedly felt while riding. 10w Belray will make fork feel more harsh than ATF.
My preference is 5w Belray. I find it makes fork more comfortable & wheel follows road surface better allowing better control, especially heeled over on bumpy curves.
Belray was recommended to me by my coworker & his friends that are racers & suspension gurus. It seems slipperier than ATF to me.
On a side note, the damper piston oring creates great stiction. LP Williams phenolic rings cures that 100%. Well worth the higher cost.
Genuine Leak Proof Classic fork seals really do resist leaking. They also have much less stiction than normal seals such as Emgo.
I most strongly recommend both these no matter what weight oil you choose
Also make sure the fender stays fit tension free. If stays have to be flexed to get bolts in it will increase stiction.
These forks have reputation for harsh action. The above will allow fork to work to it’s potential. When set up like this they really feel & work well. The better ride & improved handling substantially reduces fatigue on longer rides. I was surprised by that.
I use the recommended 190cc.
Don
Hi Peg thanks for your response, I purchased some aftermarket seals and installed them they slid right in perfectly they seem to fit well but they’re definitely not like the original ones that I took out that have a metal plate on the top that basically hold them in place. Seals seals went in almost a little too easy although they were snug. I was a little concerned that they would not seal that’s why I asked the question. I think I’m going to take Don’s suggestion and buy those seals from LP Williams overseas.Hi
The leakproof seals will need to be purchased as a conversion kit for 76 forks.
If you fit them correctly to stanchions and fork sliders with surfaces in good order, it is likely that you will not have to worry about leaking forks again.
If you are feeling experimental the amount of oil in the fork can be varied, once the forks are properly sealed, the amount of compressible air in the top of the fork can be changed by adding or removing oil.
If you are of heavy build or ride 2 up regularly, more oil can give a stiffer spring effect, inversely, if you are of light build less oil can give a softer spring effect.
Of course care must be taken that the damper mechanism is not out of the damping oil at full fork extension if you lower the oil level significantly
Small changes in oil level can have a noticeable effect.
Regards
Peg
HiHi Peg thanks for your response, I purchased some aftermarket seals and installed them they slid right in perfectly they seem to fit well but they’re definitely not like the original ones that I took out that have a metal plate on the top that basically hold them in place. Seals seals went in almost a little too easy although they were snug. I was a little concerned that they would not seal that’s why I asked the question. I think I’m going to take Don’s suggestion and buy those seals from LP Williams overseas.
Cheers
Thanks Don I already went through the process of putting the new seals and the O-ring in just having second thoughts about the ones that I did use I am going to swap them out for the better product. I haven’t put the fork oil in yet and my bike is 100% apart so it won’t be a big deal to swap them out. Thanks again . CheersHi 76barnfind, Sounds like you got the Leak Proof seals. I don't know the difference between soft & hard ones. I've installed several sets of Leak Proof, but always used the genuine Leak Proof in their packaging. I'm afraid to use any others as these have worked so good.
Absolutely worth taking dampers out to use phenolic LP Williams damper rings. Spread them gently, don't wind them on, but spread with thumb nails. Lube them well. They will fit damper very loose. You'd think they'd not work good, but they are fantastic.
You can just unscrew allen bolt in slider & push damper rod out the top. Keep track of dowty washer in slider, but it generally stays put. Very careful visual inspection through bolt hole & you can see if washer is in place. I just did the through the top on a set I installed recently. Hold slider full up. Push long screwdriver or piece of rod/dowel up bolt hole. Engage rod into bolt hole of damper rod. Guide rod down to slider. I often use a 3/8 drive spark plug socket & extension from top to help push down damper rod. If handle bars are in place restricting access Just use a long rod or screwdriver. This method you don't have to unscrew the retainer nut on stanchion or remove slider & have to work seal over fork end.
Sealant on allen bolt head is always a good plan. I've seen so many leak even with new dowty washer. Sealant on spring nut threads also or they will leak.
Gaiters are a good thing. Keeps water, dirt, bugs at bay. I don't use them because my bike didn't have from new. I want to keep it visually stock.
Don