forks for a gs750

[lee]

i was just wandering how much you can lower the front forks with out them bottoming out. i have lowered the back and now want to lower the front to match. i want to lower the front buy 2" if possible. it looks to me that if i take the frok tubes apart i could cut the bottom spring and just let the top fork tube just slide on down a little is this true? if not is there another bike that has the same upper fork tubes as a 78 gs750 but two inches shorter i could swap mine out for. this is only going to be used to run around town and to ride to work i have another bike for long rides. any help or fresh ideas would be greatly appreciated.

[Billy Ricks]

You would be better off seeing if the forks can be raised up in the triples.

[lee]

Gs forks

The handle bars will slide up about half a inch I need about two inches.

[tukn20s]

I would not recommend lowering the forks that way. The previous owner of my gs750 lowered them that and I'm very unhappy with it. The forks will actually extend to the original height still, so there will be a dead space causing them to slam down when you hit larger bump. I suppose it might work with a different spring.

There is a proper way to lower them but I don't know what it is. I too would like to find forks that are approx 2" lower.....so if anyone can shed some light as what forks would swap into our bikes or the proper way to lower them that would be great!

[trippivot]

2" will be a breeze. you put a spacer under the dampening rod - you may not want to cut the main fork spring unless you HAVE to. ( total weight considerations) some times a short spring made from another fork spring in conjunction with a spacer OR instead of a spacer... you can probably get 4" before having to really compromise.

I also weld 2 of the dampening rod compression holes for added hydraulic stiffness.

you may get not over 3" before bottoming out

but remember modified bikes = modified problems every one is different

as for tukn20s response I think your forks are dangerously wrong - it should be seriously spring loaded at rest and fully extended. no dead spaces .

[trippivot]

You would be better off seeing if the forks can be raised up in the triples.

doing this is easy but changes the trail value,center of gravity and dynamic rake of the bike.

trail is like "toe in" on a car nothing quite like maiking a wobble and freaky turning problem.

Oh plenty of people do it but trail is like "toe in " on a car it makes the bike go straight on it's own and feel stable.

shimming the dampening rod internally keeps the stable geometry in place for a lower - smooth ride.

[tukn20s]

Yes I agree that the forks on my bike are dangerous and I have not rode it this year because. I have been looking for new forks, but if I can properly correct what I have that would be great.

So do you match the size of the spacer to the amount you are trying to lower the bike? Is there anywhere to find a picture or diagram of the process? I personally am not familiar with the forks, i've never had one apart.

[tukn20s]

Ok, I found a diagram of our forks. Maybe that will help explain how the spacer is used.

[Don-lo]

The drag racers I worked with would use lowering blocks: precision blocks in a kit that came with INSTRUCTIONS. It was weird to put something into the fork and then have the forks be shorter. They were stable, but they used up suspension clearance. If you find them (dragracers supplys?), I would really recommend 1" blocks and sliding the forks up .5".

[tukn20s]

I agree that adding something to the forks seems strange that it would lower it. That is why I was confused since i've never had a fork completely apart. However, I did find a couple step-by-steps that clear things up. They are for the older yamahas, but should be the same basic concept for our bikes. Pretty straight forward and easy process. Here are the links if anyone is interested.

http://www.chopcult.com/forum/showthread.php?t=7330

http://www.xs650chopper.com/2009/06/mulligan-machine-lower-your-xs650-forks-low-buck-garage-tech/

[trippivot]

it is similar to the links however a oil hole is not necessary for the GS. just a spacer under the dampener rod

all the spacer does is prevent the inner dampening rod from fully extending out of the bottom of the main fork tube. Simply making it extend 1 or 2 inches less than it normally would fully extended. the main large fork spring will be the same distance too long up at the top. remove the progressive windings first. (little narrow coils) not the wide coils. use a cut off wheel making sure not to over heat the spring.

1 -1 ratio spacer length to desired lowering distance

[tukn20s]

Thank you! Any suggestions on what type of material to use for the spacer? I figured steel or aluminum, but i've also heard of people using pvc and other plastics.