XJ750 Maxim Fork Swaps

Hi everyone, I've done some reading and still cannot come to a conclusion about my options here. There's a chance that once I get my other bike running this summer, and therefore have one to ride and one to tinker with, I will want to go the Clip on/Rear sets route with this bike.

If I do that, I'm going to have to lower these forks about an inch to slide the clip ons onto the fork above the top triple tree (I understand I could place them under the triple, but I think they'd be too low).

My problem is that I have these silly air assist forks.


As you can see, the right fork in this picture is in its normal position. the left is pulled down a bit. It seems that the two air assist "surrounds" on each fork that connect the air tube are immovable, and not removable. Or are they?

I could not slide them up, or down, and so it is my belief that if I want to lower these forks by pushing them up the triple a little (A bit less than an inch) that I'd need an entire new set of forks. So, if I cannot remove this air assist function, Are there any direct swaps from other XJ's that I could use?

Thanks everyone.

 

the air line crossovers are sealed to the fork tubes by two O-rings. they will slide on the tube, they are just stuck. here is a fork size chart I found recently that will give you some idea of other forks you could use.

http://www.dotheton.com/forum/index.php?topic=1090.0

I think it would be easier to put a set of clubman bars on it instead.

FU

 

Thanks for the link. It seems to me that you're saying I can move the airline crossovers up or down an inch with no ill effects? but there's gotta be an oriface that goes directly into the fork right? The air that would normally get pumped in has to go somewhere. Wouldn't moving the crossovers disrupt the O-ring seal?

You're probably right about the clubmans, but I don't prefer them. Also, I'm looking to stay in the XJ Family of forks because I don't want to have to machine spacers for the wheels and have a new axle made. At that point I might as well just pay to have spoked wheels, and I'm not interested in doing that.

 

Actually, the air joints are held in place via a thin retaining ring (below the joint) that prevents it from moving downwards:

HCP12315 Aftermarket inner fork tube air joint RETAINER RING, this narrow, stainless steel wire retainer ring fits in the machined groove on the tube and prevents the air joint from migrating along the tube. Use 1 per tube, fits either left or right air joint on the following models: XJ650 Turbo, 1982 XJ750 Maxim, XJ750-D, XJ750-P (24L model), and XJ900RK and RL models. Each:


The upward movement of the air joint is restricted by the rubber spacer under the crown bracket, and between the two items, the air joint is "locked" into its proper position, as with your right side joint.

On your left side joint, you could move it upwards a bit (their internal O-rings are a tight fit to the tube, and can become "rubber-seized" over time, but some penetrating oil/WD40 might help loosen it). HOWEVER, once you move it "upwards" even a little bit, the air bleed hole in the fork tube will become exposed, and leak fork oil everywhere.

So you're kinda stuck with the air assist function and tubes and the stock tube height/placement within the steering brackets.

1983 XJ750 Maxim/Midnight Maxim fork tubes are the same and a direct swap, and they do not use the air-assist feature.

 

You're the man Len! Thanks so much for the information. If you have any of those '83 midnight fork tubes laying around, let me know I may definitely be interested in taking them off of your hands.

 

there are a couple sets on ebay right now...

http://www.ebay.com/itm/FRONT-FORKS-SHOCKS-1983-YAMAHA-XJ750-MAXIM-XJ-750-83-/141550637164?pt=Motorcycles_Parts_Accessories&fits=Year:1983|Make:Yamaha|Model:XJ750|Submodel:Maxim&hash=item20f513506c&vxp=mtr

http://www.ebay.com/itm/1982-Yamaha...Parts_Accessories&hash=item58bf2cb003&vxp=mtr

FU

 

you can easily solder the air holes in the forks shut and just forget about them, then move the forks where you want.

 

Brosef, you don't need the lower fork tubes, just the chrome inner/upper tubes......everything else will be the same (the cap bolts and damper rods differ, but they're easy to swap out). But you'd actually be better off buying a set of used forks than all the bits to convert your forks over.....

 

If you want to be economical you can thoroughly clean and degrease the upper fork tubes, and fill the air passages with a two-part epoxy (use masking tape as a backer on the inside of the fork tube), or solder it closed as Polock mentioned. That will seal off the opening and you can then despense with the air joints. If you are handy with machine tools you could drill out the passage, tap it, and install a short grub screw to fill the hole for an even more permanant solution.

If you have a bit of money to spend on the project you're really better off swapping in the front from a newer motorcycle. http://xjbikes.com/forums/index.php?threads/xj650-to-r6-front-end-conversion-step-by-step.40332/