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Rear Shim Advice

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Old 05-07-2007, 10:17 AM
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Rear Shim Advice

For those of you who have risen the rear ride height by adding a shim on the shock mount, did you all machine the shim yourself (I have the CAD of Greg's shim), or has anyone found washers thick enough to do the job? I'm probably lookin to go with the standard 5mm for starters and then adjust from there. Thanks for the help.
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Old 05-07-2007, 10:20 AM
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I use a stack of fender washers I bought at the local hardware store for pennies. I even cut a notch in them so I don't have to completely remove the shock to make adjustments.
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Old 05-07-2007, 12:17 PM
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I use a 1.25" washer cut with a hacksaw/dremel into a "U" shape to allow me to slip it in without removing the entire shock bolt. Works great. Just loosen the shock nut, and lift the bike to allow the rear suspension to 'droop'. You can then just slide it in. Use 2-5 of em to get the ride height adjustment you're looking for.
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Old 05-07-2007, 02:22 PM
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i just used a stack of stainless washers that fit the bolt snuggly and angle grinded a notch so they would slip on... its more adjustable that way.
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Old 05-07-2007, 02:46 PM
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Just a quick question on this topic, will this (rising rear height) make the shifting easier or no effect? And what's the main reason many people are doing this? Thanks a lot!!
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Old 05-07-2007, 03:05 PM
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It only affects ride height in the rear, which makes the bike steer quicker. Shimming the rear has no effect on shifting.
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Old 05-07-2007, 03:14 PM
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i used a chevy front end alignment shim
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Old 05-07-2007, 03:43 PM
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Thanks a lot everyone. After exams are over and I have some free time I'll be playing around with it.
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Old 05-07-2007, 05:48 PM
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I'd suggest using/testing with multiple shim heights before bolting everything back in place... I put 6mm in right from the start, put everything back together and then realized I couldn't put my feet flat on the ground afterwards!!! In the end, 4mm worked nice for me.... good reason to use a few washers instead of having someone machine a plate for you. A small change at the shock makes a noticable difference elsewhere!!!

J.
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Old 05-08-2007, 10:37 AM
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Relating to the present shim question, what setting do most of you have the rear spring adjuster at. Should I crank it for max preload? I dont know what to do, except that with my new undertail, I dont want to run the risk of tire/exhaust impact.
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Old 05-08-2007, 11:22 AM
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I tried to get a 6mm shim in and it wouldn't go as the suspension linkage was contacting the pipe (not sure how some of you got yours in there) so I settled on one that is 4.7 mm thick (or 3/16" if I recall correctly).
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Old 05-08-2007, 11:26 AM
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There should be no way the rear tire should/could contact the undertail unless you remove the shock or one of the links. There simply isn't that much travel in the rear suspension, unless your undertail is REALLY low.....
Way back when I still had the stock rear shock, even with 250 lbs of rider and a 150lb passenger...I still never bottomed the rear.

By raising the rear ride height, you put more weight on the front end. Makes it harder to wheelie(more weight on front end), gives better front end feel, and also makes turn in faster.

I run 4mm on the street and 7mm for track days.

I'm running different headers (2-bros) so I don't have the linkage/pipe interferance problem.
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Old 05-08-2007, 05:45 PM
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autoteach,

Set up your rear preload to achieve 25-30mm of rear sag. Front should be set up for 30-35mm of sag. Setting sag is always the FIRST step in adjusting suspension.

There is an article in the Knowledge Base section on how to set sag.
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Old 05-08-2007, 06:06 PM
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Crap of it is, I am still waiting for my headers, and I am just finishing up the wiring. I guess if I finish thursday with wiring, I can set my sag, prob. on the lower side, and see where that puts me with the undertail exhaust. I will have to carry my spanner wrench with me for the chicks.

"How much do you weigh?" Probably won't go over well with the chicks, I imagine I will get the "well, HE doesn't have to adjust HIS suspension before I get on." Maybe followed by my reply of, "Get a ride from him, then. oh yeah, you looked too fat for my bike."
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Old 05-08-2007, 06:10 PM
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One or two stickers on your tail section will cure the problem:

"NO FAT CHICKS"

and

"WEIGHT LIMIT: 130 lbs."
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Old 05-08-2007, 08:04 PM
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"One or two stickers on your tail section will cure the problem:

"NO FAT CHICKS"

and

"WEIGHT LIMIT: 130 lbs." "

he he, I love it
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Old 05-08-2007, 10:22 PM
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I did the rear shim thing using some large washers from Lowes I cut with a dremel - it worked great, really helping the steering. I've seen other people describe this as more flickable. Really helped reduce runout in turns.

Unfortunately, when I did some work on the forks and put them back on the hawk, I dropped the forks about 5 MM in the in the mounts and this really made the bike handle but when I ride on straight bumpy roads, the bike feels really skittish. I have to work on the bike for something else this weekend so I am going to try I changing the forks to only about 2 MM drop in the in the mounts and seeing it this creates a nice compromise.
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Old 05-09-2007, 05:58 AM
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Is your sag set correctly?
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Old 05-09-2007, 11:54 AM
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I made mine from aircraft aluminum (nice and light), a solid piece cut to shape and nothced per Greg's sight. Mine is about 7/16 inch thick. I am 6' and 1" tall, so the added height was wlecomed to me, plus it seemed a lot more flickable entering the corners. I ride with full rebound and dampening in front and back.
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Old 06-08-2007, 11:01 PM
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how big of a hole needs to be in the shim or washer?
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Old 06-17-2007, 07:19 PM
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10mm
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