Large Spine Frame XS650 / Egli / Rau / Cafe Racer

Also been wrestling with VIBRATION. I bought some clip-on weights for a GSXR. They are very heavy, had to turn them on the lathe to get them to fit the clip-ons I'm using. I can't really tell if they are quelling any vibes though...

Any other tricks out there for smoothing vibes on the hands?
 
Also been wrestling with VIBRATION. I bought some clip-on weights for a GSXR. They are very heavy, had to turn them on the lathe to get them to fit the clip-ons I'm using. I can't really tell if they are quelling any vibes though...

Any other tricks out there for smoothing vibes on the hands?

Buy a Gold Wing. BADA BOOM!! I’ll be here all week folks, try the fish. :D
Seriously, though I was surprised to find out , that grips can make a lot of difference. I have two XS650’s and one had these thin rubber grips, and for the other I purchased a set of Emgo GT grips which are kinda fat and squishy.
They are surprisingly comfortable. The first ones I bought were black ,
903CA90F-4158-4C03-8D74-EE6BE607DA67.jpeg
And I liked them so much I bought another set of them in the soon To Be Very Popular Golden Oil. ( Or as Pete likes to call them Hipster Brown)
66DF4A7A-97D1-4B14-84C8-9304FB44FE46.jpeg
 
Remember the chrome capped foam grips popular with cruisers and Gold Wings? The foam does deteriorate and get harder with age, but can be bought separately to renew them. I slid that foam replacement over the old rubber grips and trimmed excess length with a razor blade. Works very well for me! The replacement foam is Grab-On brand and sold through Parts Unlimited dealers and probably other sources as well. This makes them larger diameter and I like that but others may not.............
 
Fork seals replaced.

Had the 18thooth 530 sprocket machined down to 520.
Sprocket swapped. 1mm, .039" clearance to the clutch rod! Test Drive, not going insane yet. No issues.
305.43mm long (shortened) IMG_1286.JPG Sprocket clearance IMG_1287.JPG Sprocket clearance 1mm MG_1289.JPG

Got about 300 RPM improvement at 70MPH. Now it is now 4500rpm at 70. I like this gearing. I might be able to keep up with commuter traffic now.

Vibes: I bought the big rubber grips and installed them (Grand Tourismo grips from above). Had to cut off the ends for the clip-ons. There is still considerable vibration. But - for what they are, they work really well. Cut the total vibes in about half. The size will take a little getting used to.

After the last ride, I checked oil and it was a little low. I had topped it off with a convenient, random oil (hind sight, I think it was a synthetic). Figuring that I'm still going to be changing oil within 50 - 100 miles, who cares... Clutch slip.

I also noticed the clutch throw at my handle seamed to go almost full extension before final clutch completely engaged.

Response:
Adjusted the clutch rod.
Rod was 306mm, now 305.43mm = .57mm shorter. (Was shooting for .5mm / .020".) In inch: 12.047", now 12.025" = .022" shorter.

Oil change.
Using Motul 4T 4-stroke motor oil. 3000, 20-50W
JASO MA Mineral oil. Learned alot about modern oils.
No more clutch slip. Think I will stick with MA or MA1.

While I have the side case off, changing sprocket and clutch rod length, oil drained... Why not remove the Starter cover and try to stop a minor leak. I'm not 100% sure where the oil is coming from, but suspect it is this starter plate - behind the counter sprocket. Thought I had a spare gasket, but no. So, I was very careful and able to recover the gasket, then use "form a gasket" on both sides of that.
Should be good to go, right?
Starter Cover IMG_1290.JPG Starter cover Separated IMG_1291.JPG
Unfortunately, it still leaks oil. It could be from some other location. However, I noticed that one of the six bolts, would not safely hit 7 in-lbs. It got up to about 6 (soft, doesn't feel like it is getting tighter, like the others...) and the others were safely at 7 (felt strong, like they could take more). So, thought I would try it.
Starter cover Separated suspect.JPG Starter cover Separated suspect Screw location.JPG
While disassembling the plate, it did seem to have oil between the gasket and the cover, in that general area. That one screw could be the root cause...

Hmmm... Is that a blind screw hole (bottom left screw)? I might need a bottoming top, then add helicoil... TBD...
If it isn't from that area... thoughts? Suggestions for finding the leak location?

Now sitting at exactly 100miles on the odometer.
 
Last edited:
Read through your build with some interest. Kudos for the magnitude of the project and your focus on weight minimization. I've been on similar quests over the years.

Re vibration: an old farm tractor knocked up a paint shaker and the XS650 was born. The nature of the beast... probably exacerbated by eliminating the long thru-bolt and bottom of the conventional frame. One of my motors has some long ago PO damage in the form of a hairline crack in the case in vicinity of the top rear motor mount. Impossible to TIG weld without complete disassembly and sterilization as it sucks oil into weld bead otherwise. So i relieved the crack a bit with the Dremel and JB Welded it to seal it and omitted that mount to frame. So far so good, but just sayin'...

The starter cover plate you mention above is a notorious leaker. It's holding back all the oil. Permatex ultra copper helps to some extent including embedding the hex bolts in it but these bikes usually mark their territory anyway. Cardboard floor protectors are cheap fortunately.
 
Leaks... An observation, It doesn't seem to leak if standing vertical. If slightly over, like on the side stand, it will leak... Oil level is correct per dip stick...
(This could also be related to running / not running, hot / cold, poor sealing... Porous materials?)

Vibe... This is my first time to own/ride/build anything with the XS650. I can say - the level of VIBE was not fully understood until now. :unsure:

Wrestle with it a little more over the weekend.
 
Took the bike for a 50mile round trip run. Ran well. 150miles on the odometer now. Just before I got home the tail light / license plate frame/bracket broke off.
Here is a shot at midway through the ride.
1 IMG_1303 Saturday morning ride to work.jpg
When I got home... something missing.
2 IMG_1304 something is missing.jpg
Here is the assembly. The screws to mount it were designed for quick release and axially mounted. With the vibration, a resonant frequency, fatigue, and snap. Both left and right side snapped. Those were slip fits, but with just enough wiggle room.
3 IMG_1305 OMG.jpg 4 IMG_1312 Cracket.jpg
Initial design:
5 IMG_1306 current CAD.jpg
Perfect excuse to fix a couple of things. I wanted to tuck the frame up under the seat a little bit more, even with the redesign it won't be perfectly hidden though. Clean up a couple of other details.
IMG_1345.JPG new subframe assy a.JPG new subframe assy b.JPG new subframe assy c.JPG new subframe assy d.JPG
Not all worked out yet but getting there. Started fabricating a few necessary parts.
IMG_1350.JPG
 
That bike is off the chain!!! Doesn’t look very comfortable for a old goat like me. But what a beautiful bike. Great job.
 
Rephased crank, I'd love to do that (I agree, I think that would be the ticket for the vibe issue). I tried to contact Hughes and the response was basically, "we are too busy".

Are there other places that do that work? (I do have an extra engine waiting to be rebuilt... :) )
 
Rephased crank, I'd love to do that (I agree, I think that would be the ticket for the vibe issue). I tried to contact Hughes and the response was basically, "we are too busy".

Are there other places that do that work? (I do have an extra engine waiting to be rebuilt... :) )
Heiden tuning in the Netherlands, and Smedspeed in the UK for sure. A rephase is in reality just a crank rebuild, and assembled "3 teeth off" on the spline in the middle. So basically anyone skilked in overhauling 2 stroke cranks should be able to do it, like RD/Banshee, snowmobile, jetski cranks. If you also want the crank re-balanced for the rods and pistons you want to use, it gets a little more complicated.
In any case, make sure you end up with crank and camshaft rephased "the same direction".....
Smedspeed has a good writeup here: http://www.smedspeed.co.uk/tech.html
And while the crank is out, there is always the option of boring out the cases for an 840 or 880 cylinder :)
 
Wow lot's of CAD skills there, very cool.
Might want to take a page from Yamaha's design book and get some sort of rubber mount in there. No engineer but I think the problem is the tail is at the end of a long arm and vibration amplitude increases the further you get from the engine.
Maybe If you use the top center mount as a fulcrum and let the bottom two flex a bit, it would allow the vibration to be absorbed?
 
Back
Top