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Sherco 80


alan bechard
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Al,

Lane Leavitt took a broken black clutch lever and added a gob (carefully shaped) of epoxy to the end of it and Debbie was able to pull it in all the way to the bar with one finger, actually pretty trick. If you do not understand I know Lane would send you a picture.

Wayne

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Alan,

That little motor on the Sherco 80 (100 cc) will really go when you wind her up! They are just a bit less than the 1.25 and I won our last club event on the wifes 1.25 last month.

Some type of air inlet or throttle restrictor may be in order until he gets used to the power and using the clutch so that he doesn't flip it!

I estimate around 1/3 to 1/2 throttle would be a good start!

There are several small kids that ride full size bikes though, the Mizell kids come to mind. Even the older ones probably don't weigh 80lbs soaking wet.

An old Montesa rider once told me that is doesn't make any difference how much the bike weighs as long as the weight is on the wheels. Not sure exactly how much wisdom is in that?

Oh by the way, the Delta link off the '04 big bikes has a greater leverage ratio effectively softening the rear suspention. I suspect that they may not have used this part on the smaller bikes. If you shorten the swingarm it will have the opposite effect. The part costs about 65 bucks and I think I would try that first if it seems too stiff for his weight. It should bolt right on.

After that you can start grinding on the springs a bit, front and rear, if you think you need to soften it up more. I can tell you how later.

If you can get with Ray P. I am sure he could supply some input as far as how it is all working(watching him ride). Ray is a good engineer! And always wants to show it!

All these are easily done and undone. Just try not to hack up anything major at first.

Mark :hyper:

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Ok Charlie, here goes!

I will remind you that I am not an expert at this and opinions may vary!

First you have to understand that the tension of the spring is set by the cross sectional diameter (area) of the wire (spring steel) used to make the spring. If you looked at its cross section it would be pretty much round for most springs used in forks.

To reduce the tension you must reduce this area, changing this cross section from a circle"O" to a "D". The force of the spring will be reduced proportional to the amount of material removed. The limit of material that can be removed safely is about 25% of the total material.

This must be done evenly throughout the length of the spring to prevent creating stress points causing the spring to break prematurely.

The best way I have found to grind these surfaces evenly is to chuck up the spring in a lathe and use a steel rod through the center that supports the length of the spring to a stand on the other end. Set the lathe to turn at a slow speed of about 50 rpm.

I then use a automotive high speed body grinder with a 6 or 8 inch flexable abrasive disk of 80-120 grit and work evenly along the length of the spring to remove the amount of material required. Grind opposite the direction of spring rotation and be consistant with speed and pressure along its length. Keep moving! Do not create hot spots as this will weaken the spring as well.

You can stop at any point and slide the spring into a fork leg assembly and using a set of bathroom scales, see how much force (in pounds) is required to compress the fork vertically to a predetermined (marked) distance, lets say 3 or 4 inches on the slider. Of course you need to measure this force before grinding as well to see how much change you have made.

You will have to turn the spring around to grind the part that was inserted into the lathe chuck too.

Both springs should be matched in force required to compress the spring. A good eye will tell you when all the flats on the springs appear equal width.

A final sanding with 180-240 grit will polish the surfaces on the spring to reduce internal friction as the spring moves in the fork when used.

Just don't grind too much cause you can't put the metal back!

Wash and clean everything so that no small metal particles get in the forks and reassemble.

I need a beer now!

Cheers! :rolleyes:

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Ok Charlie, here goes!

I will remind you that I am not an expert at this and opinions may vary!

First you have to understand that the tension of the spring is set by the cross sectional diameter (area) of the wire (spring steel) used to make the spring. If you looked at its cross section it would be pretty much round for most springs used in forks.

To reduce the tension you must reduce this area, changing this cross section from a circle"O" to a "D". The force of the spring will be reduced proportional to the amount of material removed. The limit of material that can be removed safely is about 25% of the total material.

This must be done evenly throughout the length of the spring to prevent creating stress points causing the spring to break prematurely.

The best way I have found to grind these surfaces evenly is to chuck up the spring in a lathe and use a steel rod through the center that supports the length of the spring to a stand on the other end. Set the lathe to turn at a slow speed of about 50 rpm.

I then use a automotive high speed  body grinder with a 6 or 8 inch flexable abrasive disk of 80-120 grit and work evenly along the length of the spring to remove the amount of material required. Grind opposite the direction of spring rotation and be consistant with speed and pressure along its length. Keep moving! Do not create hot spots as this will weaken the spring as well.

You can stop at any point and slide the spring into a fork leg assembly and using a set of bathroom scales, see how much force (in pounds) is required to compress the fork vertically to a predetermined (marked) distance, lets say 3 or 4 inches on the slider. Of course you need to measure this force before grinding as well to see how much change you have made.

You will have to turn the spring around to grind the part that was inserted into the lathe chuck too.

Both springs should be matched in force required to compress the spring. A good eye will tell you when all the flats on the springs appear equal width.

A final sanding with 180-240 grit will polish the surfaces on the spring to reduce internal friction as the spring moves in the fork when used.

Just don't grind too much cause you can't put the metal back!

Wash and clean everything so that no small metal particles get in the forks and reassemble.

I need a beer now!

Cheers! :rolleyes:

Thanks!

I thought beers were only referred to as "cold ones" in Texas. :lol:

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GEE DAD, I NEED A NEW HELMET NOW TO MATCH THE NEW BIKE! MAYBE ONE OF THOSE CARBON ONES WITH THE FANCY PAINT LIKE RYAN HAS! YOU COULD EVEN PUT MY NAME ON THE BACK! :D  :rolleyes:  :D  :lol:

PLEEEEEEEEEEEEASE!

Shuddup and eat your potatoes, because they're all you're getting until your bike is paid for.

And go cut the lawn! :P:D:D

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POTATOES!!!!!!!

All he gets is the SKINS!!!

Nahhh, it was reasonably priced and in excellent condition, couple of this and thats to play with but that comes with the territory.

Thanks to Brian for getting it for me! Even if we cannot figure out how to tell each other where we will be!!!!!

The chop saw is coming out tomorrow though I think!!!! I got practiced up on a GSXR frame today for Action so it is Swingarm time!!!

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