Triumphrat

BlueBird · 05-26-2007

I haven't been posting much recently, but maybe you guys can help me out a little.

My right front fork is leaking oil. I'm planning on upgrading the stock suspension within a month, so I'll be taking the forks apart at some point anyways. Any clues on why it may be leaking (enough to pool up on the ground over the past 10 days while I've been out of town)? or am I going to have to wait until I take it apart to see what needs to be fixed/replaced?

Any advice is welcome. :hammer:

Scot03Bonnie · 05-26-2007

Can you see where it's coming from? Running down the outside of the fork leg from under the top of the slider? Oily dirty film on the stanchion tube? If so that is probably the seal in the top of the slider. See any rock chips or dings on the stanchion tube where it slides? That could be the cause, a nick in the seal.
But, usually a leaking oil seal will leak only while the bike is in use, the oil comes up when the fork is under compression. I wouldn't expect a pool of oil from that after the bike sits.
It could be coming from the bolt in the bottom that holds the damper rod, which is something you'll have to loosen anyway if you disassemble the fork. Those have a copper crush washer under the bolt head which may have worked loose and should be replaced whenever the bolt is removed. That would have the oil coming out around the axle.
It could also be a porosity in the slider casting but that's a lot less likely.
If you only change the springs and oil for your upgrade, you won't need to remove any of these parts to do it, only pull the tubes out of the yokes and dump out the oil/replace with new, but if your bike has a lot of miles you should probably replace the oil seals anyway. To get them out you have to undo the damper bolts (best done with an air impact) then you remove the little keeper clips and washers, and bump the seals and bronze bushes out by "slide hammering" pulling up hard repeatedly on the stanchion tube with the slider clamped in a vise.
I recommend having a Triumph manual or the Haynes book on hand and read that section before you start.

Baltobonneville · 05-26-2007

Since it still should be under warranty, why not have the dealer fix it at no charge? This also documents the problem. Maybe the mechanic can/will change the oil and drop in the new springs if he has to take it apart.

Jimbonnie · 05-26-2007

Erica, definately have the dealer correct the problem.

My buddy, who owns a 2001 Bonnie, developed a leak from one of his fork seals. We intended to repair it ourselves and tried to remove the lower bolt that allows you to separate the upper tube from the lower leg, but no dice.

We brought it to the dealer and he fought it for hours. Apparently the bolt was "glued" to the damper rod by some overzealous assembler at the factory, and when the bolt finally did come free it brought the treads from the damper rod along for the ride.

So how his fork seal replacement has turned into a $350 adventure; don't let this happen to you.

As an aside, I read an interesting article that claims you can pop out the fork seal without separating the upper tube from the lower leg. Basically you remove the forks from the bike, fill them with engine oil so there is no air with in them, and compress the fork in a press or by some other method. The engine oil, being incompressible, forces out the seal by hydraulic pressure. Of course you have to remember to remove the retaining clip first.

BlueBird · 05-26-2007

Thanks for the responses guys. I'm thinking I'll take it to the dealer and see if its under warrantee.