XS11 to thunderbolt trail affects

[fredintoon]

Raising the rear

ok good to know. I think I am going to try to raise the rear a bit. If I need to I may make fork extenders like xschop did. Tho I dont think he ever ended up needing them.

Hi joep7,
I got a set of NOS shocks at a swapmeet for a steal.
They are 14" eye to eye but WTF, I put them on anyway.
And Oh my, look at the shaft angle! So I took 'em off again.
Two concerns:-
1) Will running at that extreme of an angle accelerate the wear on the U-joint?
2) The U-joint ain't a CV joint; it goes fast then slow twice each turn and the effect increases with the angle.
(Note:- so does a RWD car's drive shaft but it has two U-joints so they cancel out)
So will the increased fast/slow ~12 times each wheel turn actually notice?

[joep7]

Hi joep7,
I got a set of NOS shocks at a swapmeet for a steal.
They are 14" eye to eye but WTF, I put them on anyway.
And Oh my, look at the shaft angle! So I took 'em off again.
Two concerns:-
1) Will running at that extreme of an angle accelerate the wear on the U-joint?
2) The U-joint ain't a CV joint; it goes fast then slow twice each turn and the effect increases with the angle.
(Note:- so does a RWD car's drive shaft but it has two U-joints so they cancel out)
So will the increased fast/slow ~12 times each wheel turn actually notice?

I am doing a full chain conversion so wont be an issue.

[James England]

I fitted progressive front and rear springs on my XJR1300. The rear spring manufacturer advised raising the font fork tubes in the clamps by 1cm. I tried the new rear springs without doing so...then tried it with the forks raised. It certainly does make a big difference, I found. The steering was much less precise with the fork tubes NOT raised and, of course, I now ride the bike with the tubes raised, as advised. For what it's worth........ The XJR is quite XS-ish and also a large, heavy bike......

[MaximPhil]

I fitted progressive front and rear springs on my XJR1300. The rear spring manufacturer advised raising the font fork tubes in the clamps by 1cm. I tried the new rear springs without doing so...then tried it with the forks raised. It certainly does make a big difference, I found. The steering was much less precise with the fork tubes NOT raised and, of course, I now ride the bike with the tubes raised, as advised. For what it's worth........ The XJR is quite XS-ish and also a large, heavy bike......

Hi James,
Enough XJR1300 talk....we are all envious already
Why Yamaha refuses to bring that model to North America is still a mystery to me. I fell in love when I first saw one in Paris in 2000.

Phil

[James England]

Hi James,
Enough XJR1300 talk....we are all envious already
Why Yamaha refuses to bring that model to North America is still a mystery to me. I fell in love when I first saw one in Paris in 2000.

Phil

Heh, heh heh!

[James England]

I still prefer the looks of my old XS though. They are similar bikes in many ways. I still miss this one....

[fredintoon]

I am doing a full chain conversion so wont be an issue.

Hi Joe,
well, now you tell us.
seems to me you have swapped shaft problems for sprocket problems.
the biggest sprocket that will run on a chain converted XS11 is 13T.
The smallest that will run nice is a 15T and that's dodgy; my Suzi GT750 threw it's chain and trashed the crankcase on it's 15T sprocket.
What you could consider is a 40 series double-row chain, that size chain would run a 16T sprocket in the same space.
Back in the 1980s you could buy kits to make the conversion but these days you'd most likely have to DIY.

[MaximPhil]

I still prefer the looks of my old XS though. They are similar bikes in many ways. I still miss this one....

Hi James,
Thanks for the pictures. Both lovely bikes.
Your old house looks as though it could do with a facelift or atleast point a few bricks

Phil

[joep7]

Hi Joe,
well, now you tell us.
seems to me you have swapped shaft problems for sprocket problems.
the biggest sprocket that will run on a chain converted XS11 is 13T.
The smallest that will run nice is a 15T and that's dodgy; my Suzi GT750 threw it's chain and trashed the crankcase on it's 15T sprocket.
What you could consider is a 40 series double-row chain, that size chain would run a 16T sprocket in the same space.
Back in the 1980s you could buy kits to make the conversion but these days you'd most likely have to DIY.

I am working out the sprocket issue currently. I work at a company that builds motorcycle parts and have access to some really smart ppl and expensive equipment that will help with the machining of the conversion itself.

[fredintoon]

I am working out the sprocket issue currently. I work at a company that builds motorcycle parts and have access to some really smart ppl and expensive equipment that will help with the machining of the conversion itself.

Hi Joe,
that's great! If you can hog the case out to fit a 17T sprocket all you'll need to find is a cast disk brake rear wheel from an XS650.

[joep7]

So I was trying to figure out a way to get a little more clearance under the bike and also allow me to use the undermount shock (a cross frame tube gets in the way. )

My thought was to copy what buell did by offsetting the swingarm a bit.

This lowers the swingarm by about an inch.



Will this be safe? What may it interfere with?

Obviously dimensions are not accurate as well as exact mounting.

Frame for reference....shock is hitting the lower rear brace below the swingarm pivot.

[joep7]

My conundrum...

[WMarshy]

Sorry, not going to find a standard answer here on your issues, only some opinions. I have read others using a ZRX swing arm and maintaining the dual shocks. Only a few people have used a monoshock and once you travel down that path everything is custom.

[TopCatGr58]

The designs I've seen have had the monoshock UP above the battery box area, not down below the frame/engine. I don't know much about the swingarm your using, but can it be flipped upside down so that the shock/spring is on top so you can secure it to the frame under the tank???

T.C.

[joep7]

I'm ok with not getting standard answers