Thought I'd share, all cred to "Jake" the author and the xv yamaha site I lifted it from,
 

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  • Amazing List of Fork Tube Sizes, Neck Bearings, Axle Diameters.PDF
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I am building a cafe from a 1976 TT500.

Here are my proposed modifications:

1979 XS650 swing-arm and XS650 18" Rear wire wheel & drum brakes.
I would like to use 1979 XS650 front forks, wheel and brakes but the stock triple tree
is 36mm and the XS650 forks are 35mm.

Is there a 35mm triple tree that will fit the TT500 steering stem: Upper 24x43x11, Lower 3x48x12 ?

Any suggestions for an alternative front end with 19" wire wheel and disc brake(s)?

Thanks
 
I'm not sure i'd trust that list. The only 650 they list is the 74 TX650 under 17 mm. The TX650 wasn't a 74 the 74 was the TX650A, The TX650 was a 73. It doesn't list any of the XS650's No 70-73, no 75 up.
On your 76 TT500 I think it uses the same neck bearings as the XS650. If so, the XS650 trees should fit the neck.
I looked at the parts fiche at www.yamaha-motor.com. The part numbers are different than the XS650 but look very simular. Try putting the XS trees in the TT500 frame.
Leo
 
I got a great deal on some new Sportster wheels and tires (16 and 21") and was so exstatic that I failed to think about hub width. I'm now stuck with whether or not to try and fit a Sporty triple/fork set up on my '81 hardtail, or to dump these and go with some other make of wheel (I really, REALLY want to use these wheels).

Any suggestions on the front end swap? The above info was great, by the way.

Yes presently using a sporty or dyna front wheel 4.5" approx hub width 21" on yami xs 77 and up ONLY front end width of forks will matter since the older 70- 75 are not wide enough to let you center the front wheel. I had a custom front axle machined using the stock dims for the fork clamp and the rhs fork hole. so the machining is for a 3/4" axle. this will let you use the hd front wheel. next you need to shave off 1/8 " off the mounting brackets on the 77 and up front disk caliper so that the wheel is centered next you need to make some spacers and forget about running a speedo drive b/c it wont fit. I used a hd rear speedo drive on my back wheel ( since i need it to pass inspection Alberta Canada sucks that way you US guys got it made ) any ? pm me I am working on it right now !:thumbsup: cost of parts $50 to machine axle and spacer I made myself.
 
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Builder, your wrong on the fork width on the XS650 all were the same width from 73up. I have swapped enough wheels from early to late, spoked or mag to know they all fit all forks. I don't know about the 70-72's. My 75 34 mm forks as well as the 3 sets of later 35 mm forks are all 7 1/4 inch ctc.
Where the axle goes through the forks is 6 inches wide.
And they are all wider than a Harley Narrow Glide fork. 7 inches ctc, that's what my Harley has. With 5 1/2 inches between the forks at the axle.
Even with the wide glide front end they use the same hubs just longer spacers to fit the wide glide forks.
From looking at my Harley and the xs650 side by side I can't see needing to shave the caliper mounts to center the wheel. The caliper mounts are centered on the fork, so you would need the shave the fork itself a long way before you need to shave the caliper mounts.
On te spedo drive The total width of the hub spacers and speedo drive are 1.2 narrower than the xs650 hub, spacers and speedo drive.
Ijust can't see needing any machining on the forks, maybe the axle.
Leo
 
Yes, your going right over it. In the post above yours I mentioned my "75 34 mm forks"
Just to help clarify, the 70-76 had 34 mm forks, the 77 up had 35 mm forks.
On swapping fork around the 70-73 had a shorter stem than the 74 up.
So if you want to use the later 35 mm forks you may need to add a spacer on the top to compensate for the longer stem of the later trees. Or swap the stems from an early tree into the late tree.
Leo
 
On the bottom of the XS tree the stem is welded into the tree. You grind out the weld, press the stem out. Do the same with the other tree. Now press the XS stem into the other tree, weld.
Leo
 
I am building a cafe from a 1976 TT500.

I would like to use 1979 XS650 front forks, wheel and brakes but the stock triple tree
is 36mm and the XS650 forks are 35mm.

Is there a 35mm triple tree that will fit the TT500 steering stem: Upper 24x43x11, Lower 3x48x12 ?

Any suggestions for an alternative front end with 19" wire wheel and disc brake(s)?

I used '76 TT500 triple trees and steering stem for my build. I had to lengthen the TT500 stem to fit my XS650 head-tube, but you wouldn't have to do that. The TT trees are so much lighter and cleaner in appearance. There's plenty of other (better?) fork legs to use that can be adapted to the TT500 triples.

I bored the TT500 trees out to 38mm and used '92 FZR600 fork legs. The brakes are a tight fit, but good. I used a 19" XS wheel, which required brake spacers, axle modification, and boring the fork lowers for a 17mm axle. Sounds much worse than it actually was.
 
Gomotomoto asked:
Can someone cover the process of "pressing" or swapping a stem into another front end?
XSLeo answered:
On the bottom of the XS tree the stem is welded into the tree. You grind out the weld, press the stem out. Do the same with the other tree. Now press the XS stem into the other tree, weld.
Here's some pictures to go along with XSLeo's explanation. I tried the process about a month ago; going to put an XJ550 front end on the '82 Heritage I picked up last fall. The 550 triple tree is too short so I was going to do the swap. The 650 stem came out easily, but couldn't get the 550's out, ended up getting an '82 Virago's triple tree, easy bolt on for the 36mm forks.
http://plus.google.com/photos/117439372256915490868/albums/5721041634372806897/5721041636283520418
 
thanks XSLeo & hmusket. helpful to read and see it. Wonder why the 550 stem didn't come out? maybe that weld had penetrated the tree a bit too much?
 
Yes presently using a sporty or dyna front wheel 4.5" approx hub width 21" on yami xs 77 and up ONLY front end width of forks will matter since the older 70- 75 are not wide enough to let you center the front wheel. I had a custom front axle machined using the stock dims for the fork clamp and the rhs fork hole. so the machining is for a 3/4" axle. this will let you use the hd front wheel. next you need to shave off 1/8 " off the mounting brackets on the 77 and up front disk caliper so that the wheel is centered next you need to make some spacers and forget about running a speedo drive b/c it wont fit. I used a hd rear speedo drive on my back wheel ( since i need it to pass inspection Alberta Canada sucks that way you US guys got it made ) any ? pm me I am working on it right now !:thumbsup: cost of parts $50 to machine axle and spacer I made myself.


Update: I did end up using a HD speedo and what i did is bend the speedo drive tab to fit a notch I filed on the 21" front hub. works great and the safety tech passed the bike. will take some pics for the mental picture worth a thousand words. soon!
 
Builder, your wrong on the fork width on the XS650 all were the same width from 73up. I have swapped enough wheels from early to late, spoked or mag to know they all fit all forks. I don't know about the 70-72's. My 75 34 mm forks as well as the 3 sets of later 35 mm forks are all 7 1/4 inch ctc.
Where the axle goes through the forks is 6 inches wide.
And they are all wider than a Harley Narrow Glide fork. 7 inches ctc, that's what my Harley has. With 5 1/2 inches between the forks at the axle.
Even with the wide glide front end they use the same hubs just longer spacers to fit the wide glide forks.
From looking at my Harley and the xs650 side by side I can't see needing to shave the caliper mounts to center the wheel. The caliper mounts are centered on the fork, so you would need the shave the fork itself a long way before you need to shave the caliper mounts.
On te spedo drive The total width of the hub spacers and speedo drive are 1.2 narrower than the xs650 hub, spacers and speedo drive.
Ijust can't see needing any machining on the forks, maybe the axle.
Leo

guess the proof is in building it and the caliper mount has to be shaved so the caliper brake pads will let the rotor float between them. I guess you just have to build it and think it through. but then what do i know :shrug: he he heh:wink2:
 
I stumbled onto a near perfect swap for the 1983XS650 Heritage special. Forks from Yamaha 1983 XV920, XV1000, TR1 are all a drop in fit. Almost. The triple trees are cast aluminum and substantially more massive than the XS650 but they use the same neck bearings and the stem length is equal. Fork tube dia. is up to 37mm but the axle is smaller. You could use the wheels because these are the chain drive Viragos,but I didn't like those curved spokes so I had the thicker XS650 axle big end machined down to fit the fork leg. If you do this make sure the machinist chamfers the cut for strength. A sharp corner will amplify stress possibly breaking in two, not cool. These forks have dual disc brakes that are smaller and thinner than the 650, you cannot use the standard disc, it will not fit. The calipers are the same, with left and right versions as are the mounting brackets. About 2" longer, the fork tubes can be replaced with under or over stock length. I got 2" shorter and use XS650 springs from Progressive Suspension. Their dia. is a little bit smaller than the stockers in these forks but I don't think that is an issue. The spring rate is correct. Wheel width is the same, fender mounts are the same HUGHS fork brace will fit, so will his speedometer eliminator.
At first glance they look like stock forks, but closer inspection reveals that these forks workout. I got a beautiful billet machined upper triple tree from COGNITOMOTO, they will give it whatever drop or rise you want. Any bike you want. I got mine flat raising the forks (lowering the bike) about an inch. $100 cheap!
These donor bikes are rare, and they are all different. Make sure you note the model and year because they do not all take the same fork seals.
Point of interest, the slider bearing is called out as a steel piece by Yamaha so MAYBE it could be replaceable?
 
Very useful thread. Does anyone have a drawing of a 77 XS650D stem please? I have a spare set of 38mm forks in Triumph yokes and would be great to get a stem machined in advance of pulling the forks off the XS. Thanks.
 
Frame neck
stem.JPG


stems with a tape measure
xstriples 002.JPGxstriples 004.JPG
All I had in the files.
 
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