Rear shock info? Looking for recommendations.

[16vsilverstreak]

Has anyone used the following rear shocks? Your thoughts?

http://www.mikesxs.net/product/06-3650.html 14.4 eye to eye.


http://www.mikesxs.net/product/06-3643.html 13 3/16 eye to eye.

I'm running an '03 GSXR 750 front end. I'm leaning towards the 14.4 for some added height. I'm 6'2". I've read somewhere that the XS650 tends to have rear weight bias and using longer rear shocks helps remedy that.

It's a '75, build date 12/74

[/url] image by 16vsilverstreek, on Flickr[/IMG]

[/url] image by 16vsilverstreek, on Flickr[/IMG]

 

[5twins]

You don't want either of those. Basically, all the shocks from Mike's are cheapo junk, all spring and no damping. You went through all the trouble of grafting on a good, modern front end, I would think you'd want good rear shocks to match. Call 3M at 650Central, he's got the good stuff. It will set you back $200 to $300 but that's what good shocks cost. You won't get anything but shit for $89. And yes, you do want longer than stock. Most of us use something in the 13" to 14" range.

 

[Downeaster]

I just put a set of the 650 Central 13" shocks on my '79.

Too damn cold to ride it yet, but I'll let you know.

$217 with springs installed, shipped to the east coast.

 

[jdizon]

Since this topic is about suspension.. Don't even think about buying the bronze swingarm bushings and cylinder from them. They're crap and need to be machined down to fit.

 

[xjwmx]

You don't mention year, I don't have a problem with the stock shocks for my '81. You can get them for very little (and many of them still work ). I break the reflector off and put the shock on the wrong side so that the reflector mount faces inside. Depending on year, watch out for too long shocks making the bottom mount bolt head interfere with the exhaust. Much over 13.5" shocks would do that with mine (stock exhaust).

 

[Cafe-Dave]

How much lower is the front of the XS, after the Gixxer front end? Did you reuse the XS Wheel, or put on the Gixxer 17" wheel? The Gixxer triples probably have 20mm less offset than the XS parts.

You could have removed a fair amount of trail at this point. Raising the rear end could exacerbate that issue.

I have a SV650 front end, lowered 30mm. With 340mm shocks, I'll have ~110mm to 105mm of trail with a 12/80/18 front Tire/wheel and 0.9kg/mm springs.

100mm of trail is the cutoff point for me, personally. After that it's time to go for shorter shocks or put some length back in the front end (Stiffer springs or +10mm to the installed height).

 

[16vsilverstreak]

Thanks for the info.

 

[Grinder]

Mike's shocks are like welding solid bars between the shock mounts. I found out the "hard" way. Don't make the mistake.

 

[Spockwerks]

About the bronze bushings, They need to be honed for a straight and proper fit. Warm the SA up in the oven and pop the bushes in the freezer for I/2 hour before you begin. Smear some grease in the hole and some on the bush too. They should slide in with some mild tapping from a wood or rubber mallet. Then the important step, take them to a machine shop and have them honed straight through (because they will be crooked at this point, given manufacturing tolerances plus the fact that you just hammered them together) to the proper clearance which the machinist will know or can look up. Do NOT follow the Minton mods and scuff up the bearing surface they ride on. Doing that takes a smooth mirror finish surface and turns it into an abrasive grinder that will quickly ruin your new bushes. You can see the bits of chewed up bronze wedged in the scratches of the bearing shaft. I know because I dumbly took that bad advice once. Oh, they felt great at first but it didn't last long. I tried the roller bearing conversion and found that it made no real improvement.
Then I met an idiosyncratic machinist who may have held some peculiar ideas about stuff in general, but I have never seen finer work issue from machine tools. I was a customer of his, he's gone now, but he proved the precision honing on bronze bushing theory to me about 35K mi ago. I still run those same bushes as smooth and tight as the day I unpacked them. Takes a commercial high pressure grease gun to lube them, I can stand on a regular hand pump all day and it will not budge.
Used to be only a few suppliers of the bronze bushings, now everybody has them making the issue of quality control even more dominate. IMHO it is IMPERATIVE that you have the honing done, otherwise you are wasting your time and $ for no benefit at all.
He also built me a box section swingarm that I bought with the bushings already installed & honed, Mated to Prograssive 412 12.5" shox and up front I use forks from a TR1 1,000cc chain Drive Virago. They are 37mm, look just like the stock forks, were a drop in junkyard fit. Triple clamps are aluminum so they are a bit bulkier, Shortened 2" courtesy Forking by Frank. Yamaha parts interchangeability is a wonderful thing. A Hughs fork brace for the XS650 fits perfectly, as does the electronic tach from the TR1, rear sets and all kindsa crap.
But whatever shocks you choose keep them comparable to that great front end for a balanced performance operating within it's own adjustment range.

 

[arcticXS]

How much lower is the front of the XS, after the Gixxer front end? Did you reuse the XS Wheel, or put on the Gixxer 17" wheel? The Gixxer triples probably have 20mm less offset than the XS parts.

You could have removed a fair amount of trail at this point. Raising the rear end could exacerbate that issue.

I have a SV650 front end, lowered 30mm. With 340mm shocks, I'll have ~110mm to 105mm of trail with a 12/80/18 front Tire/wheel and 0.9kg/mm springs.

100mm of trail is the cutoff point for me, personally. After that it's time to go for shorter shocks or put some length back in the front end (Stiffer springs or +10mm to the installed height).

Cafe-Dave,
Triple trees with LESS offset gives INCREASED trail, all other things being equal. I.e. no rake in the trees themselves. Less offset pulls the fork tubes, and the wheel contact patch towards the back of the bike, increasing trail. A shorter fork, and a smaller diameter wheel, on the other hand, will decrease trail.

 

[tkurt]

Another option is Hagon shocks, they run about $200 typically. They too, will advise you on a good setup for your height/weight/riding style.

Here are some on my bike:

http://www.xs650.com/forum/showthread.php?t=39276