How - TO: Lower Those XS650 Forks!!

[Punkskalar]

wow that is awesome, 65 seemed a bit high, but i think 45 shipped is a really great price.

i have read some other tutorials on this that didn't say anything about the valving and it seems like most people haven't had any problems, but those holes are obviously there on the dampening rod for a reason. can you explain how that would affect the the forks if the hole was obstructed by the spacer?

Yeah, the hole being blocked is an issue. The first few sets of forks I modded I blocked the hole, and the forks were very sluggish to respond at times to road changes. At high speeds they almost seemed locked up when trying to compensate quickly to road imperfections. I decided to start leaving the port open and haven't had a problem since. The Set Screw really helps to keep the spacers exactly where they need to be in relation to that hole. Hope that helps

[MiniDanzig]

awesome yeah, that makes sense. thanks for dropping that knowledge. i'll def be picking up a set.

[4horsemen20]

thanks for takin the time to doc all this, i'll be usin some of this knowlege real damn soon.

[cdnfire]

Thanks for this! Feel free to keep posting more how- to's, I can use all the help I can get!

[SDJose]

Very helpful for XS650 owners. Maybe someone will do a "how to" for Showa 39mm forks!

[ABP]

First off: I need to thank Hugh for being a rad guy. wonderful to deal with, man of his word, free advice and quick responses. A+ in my book.

Second: I think there is the discussion of fork oil when lowering a front end. Like in how much and maybe moving up to a "thicker" oil to help with the reduction in travel(?). Thoughts? would be cool to hear others experiences and advice.

[ABP]

Hell...any recommendation on brands would be cool too.

[Punkskalar]

First off: I need to thank Hugh for being a rad guy. wonderful to deal with, man of his word, free advice and quick responses. A+ in my book.

Second: I think there is the discussion of fork oil when lowering a front end. Like in how much and maybe moving up to a "thicker" oil to help with the reduction in travel(?). Thoughts? would be cool to hear others experiences and advice.

Thanks man, I like to know that I am treating my customers with the respect they deserve


It depends on where you ride and how you ride. If its cold as hell all year round, AND you can actually get your bike started, look at a thinner oil. I like ATF for the colder seasons, and even into the 70's really.

On my lowered forks (mine are lowered 3.25") I run 30W motor oil. Seems to be the perfect mix of dampening and not being too stiff. But, thats just me, and I like to jump sidewalks and do stupid crap like that with mine.

Really, you can use anything you want as long as it is oil based and wet. Water is no good, but ATF, Motor Oils, Fork Oils, etc... all seem to be fine. The seals seem to tolerate just about anything fluid wise, and as long as you are using about 175ML in each leg you should be good to go.

You can always try a thinner oil, and if you hate it, drain and refill with a heavier weight or vice versa.

[ABP]

Really bummed about not being able to use water since its so plentiful. I have some Bel-ray fork oil, that I figured I would try out first to see if I like the feel.

[Feen]

Just wanted to say thanks for all the knowledge... Hugh is the man!

[rekka]

Thanks for taking the time, great pics and descriptions. Another Mystery Solved.

[steves]

nice droop spacers.... a few things/tips

when you cut a spring the spring rate increases = stiffer ... which almost every motorcycle could use a little stiffer spring over stock rate

oil level/amount should be adjusted if your lowering the front end , measure with fork collased no spring fill and bleed tubes as needed then measure from top of tube down to oil (suck out excess to desired height)

IE : these numbers are just an example and let's just say we are lowering 2" or 50mm

stock length = 8.0 oz per tube = oil level 125mm (no spring fork collasped)

lowered length 8.0 oz per = oil level 65 mm (after spiring is installed oil level will rise and air spring/space is gone fork becomes very stiff /little to no travel = shitty ride )

new set up in lowered fork = set oil level at 125 mm whatever that equals in oz. is ok whats important is we retained our air space/spring in most cases oil level will need to be adjusted as per build

add oil to prevent bottoming (rememeber oil is incompressable)
subtract oil to soften ride be sure it does not mechanically bottom to ensure safe ride

when you cut a fork spring you should heat the cut end with propane tourch and make the end a dead coil and grind flat so spring will sit and work straight and smooth , cut ends tend to bend the spring and rub inner fork tube and make lots of noise

fork springs in these types of bikes "bobbers" should have about 15 - 20 mm of preload on them for a nice ride

once the bike is all together you wanna check front/fork sag
if the front end does not sag the bike will ride harsh and follow every crack/flaw in the road

front sag on a bobber should be around 1 1/4 (30mm) - 1" (25mm) this will allow the front wheel to drop into holes, bumps ect. without transfering that energy into the rider

(we find so many bikes "topped out" due to over preloading = harsh/shitty ride )

as for oil weight determins rebound .... thicker oil will increase rebound , thinner will decrease
it will not effect compression in these types of damping rod forks

atf and motor oil should not be used for many reasons ...... but if thats all ya got then run it hahaha

#1 rule of all time in any motorcycle fork NEVER EVER USE Leak Proof Fork Seals ...unless you want your forks to leak !!!!

There are many things/tricks to do to forks to make them work ,it makes a world of difference to have a fork work properly and most of all safe to ride on .

Not directed at anyone in particular... .If anyone is attempting to do their own be sure you know what your doing $125.00 or so ..is not worth ending up in a wheel chair or dead

Regards
Darren

[KsDtoday]

This needs to be pinned!

[EatACactus]

I know this thread is a little old, but does anyone know how close this procedure is on a set of KZ400 forks?

[CriminalKZ]

@EatACactus: Most of these style forks are set up the same way, whether its H-D, Suzuki, Kawi, Honda, etc. Unless they are cartridge forks. I would say it is probably pretty similar. You may use different "specialty tools" though. If you go to kz400.com I'm sure they have a service manual with the fork R&R procedure.

Also, that "Conical Shaped Spacer" is called an Oil Lock Piece. It keeps the dampening rod from hitting metal on metal by keeping oil in the bottom of the lock piece. Very important piece in these forks. Great How-To! Thanks!