Shortening the front forks on a 750LTD

I want to shorten the forks on my '83 KZ750 LTD. I probably want about a 2" drop. I'm wondering what the best way to go about doing this is.

I've been reading tutorials online about disassembling forks and cutting springs/adding spacers/etc. However I was looking at my forks today and I'm not seeing the tuts as being much of a help.

The thing is, this is one of the bikes with the air-adjusted pre-load forks...you know, the little valve under your gauges that has two hoses going into the tops of the forks. Not really sure how much I should be disassembling that stuff...

Any ideas? Anyone done this before on this style of fork?

Before anyone says it - I already slid the forks up in the triple tree. It works in theory, but the handlebars I'm using don't allow much wiggle room - I can only drop about a half inch.

leave the fork in place. under the caps there will be some sort of preload tube spacers , about 2" long that you could shorten or take out altogether. no need to start messing with the rebound spacer/springs/etc.

the only problem is that you will loss fork travel by the same amount you shorten the spacer. if the fork now bottoms on bumpy roads, then add some oil for less air volume or eventually go for stiffer spring rate

Is it honestly that simple? I'm not used to things being so easy...

I took a look under the fork caps today (they were already removed by the previous owner I suppose). There is a small air nipple and a large nut-looking thing which I cannot budge with a torque wrench.

Any idea what to look for?

Are your forks leading axle or is the axle centered under fork leg?
May look at a set of 650 forks that are same style and see how much shorter they are

Hmm, good point. That is a good alternative - but honestly, if it's as simple as TurboGuzzi makes it sound, I'd be perfectly content just using my stock forks.

I need Turbo to elaborate a little further for me.

How should I approach accessing the spacers in the top end? I took a look at this diagram and located the spacer I'm looking for...but it hasn't shed a lot of light on how to get to it. You can see in the diagram the air nipple assembly I mentioned earlier.

Any help would be appreciated. I'm taking a break for the night and would love to be able to get this completed tomorrow.

Should loosen bolt #131 (top fork clamp bolt) before attempting to remove part #44029.

Removing the spacer will likely allow more front end "sag" whereby the bike sits lower, but also leave space for the springs to clang back and forth when traversing rough terrain.

Would also assure that no bike parts such as header pipes will be able to hit the front wheel or fender when the front suspension is fully compressed.

Good Fortune!

Ah, you make a good point. It didn't occur to me to loosen the top. I'll try that first thing in the morning and see if it helps. That top piece should just screw right out, right?

And +1 for the clearance. I will be very careful. That is something that working with bicycles has taught me.

just shows you never changed the fork oil in your bikes, shame on you

so yep, just remove 44029, make sure you take the weight of the front wheel before, otheriwse bike will drop in a jiffy and cap will poke your eye,

in theory patton is right, but in practice, since most of the damping happens in extension, even on rough surfaces, after the (shorter) springs stop pushing down, there's nothing to pull the wheel down further besides weight. so unless you plan to wheelie for miles on end, not much reason to worry. as always, IMHO

I run shorter springs on most of my bikes, street bikes included, and never had issues with topping out.

get a good six point socket to undo the cap, release the bolt like patton said,

you can add some heat with a propane torch too, just dont burn the whole bike

if bike has stood out for long and cap is rusted in, then itll be hell...

turboguzzi wrote: just shows you never changed the fork oil in your bikes, shame on you

Give a guy a break, it's my first bike

Well, I tried to get the bolts off today. No luck whatsoever. All I have on hand is a standard torque wrench, and I was pulling on it so hard I was pulling the bike over before moving that $%@# screw. I smacked the wrench with a rubber mallet a bit, squirted some penetrating oil down the top, etc. etc. no luck.

Looks like I'm spending more money on a new impact wrench

Did you loosen the top fork clamp bolt first as Patton advised? If not, you will be able to twist the entire bike around in circles and not loosen the fork cap. Ed

A torque wrench is a mighty expensive tool to be hitting with mallets and using on frozen bolts... :blink:

650ed wrote: Did you loosen the top fork clamp bolt first as Patton advised? If not, you will be able to twist the entire bike around in circles and not loosen the fork cap. Ed

Yes, I most definitely did. In fact, I checked several times during the process, just to be sure I wasn't embarrassing myself :laugh:

Didn't help, though. That thing is in there solid.

Btw Killman, just to help you sleep tonight - I didn't actually smack the wrench with the mallet, merely the top of the unattached socket as it sat atop the nut. Still not the best idea perhaps.