Wednesday, April 6, 2011

Easy and Economical Fixes Continued

2011 Linkage Arm Fix

The 2011 450s have an entirely new linkage system. While the new changes are supposed to correct the problems of the older models, they do not do enough. The rear end still feels a little high. The solution for the older models (09-10) was to buy an aftermarket linkage arm that was approximately 1-2 mm longer (Pro Circuit, Factory Connection, etc). Well if you haven't looked, those are pricy ($200 and up).

What most people don't know or realize is that the linkage arm from the 2009 Honda CRF 450 is actually 1mm longer than the stock linkage arm for the 2011. So an easy and cheaper fix is to replace your 2011 linkage arm with a stock 2009 linkage arm for a fraction of the cost. I'm sure there are hundreds of guys at the track that have older Hondas (09-10) with aftermarket linkage arms and their stock ones sitting at home on a shelf. Offer to buy one off of them for $20 and you have your fix.

1mm on the linkage arm should give you anywhere between 3-8mm of sag. This will help balance out the bike more and add stability.

Cost: However much your buddies will sell one to you

Time to replace: 10 minutes

Balancing Front and Rear Suspension

Since 2009, 450 Hondas have had balancing issues in stock form. Either the front is too soft or the rear is too stiff and high. There are a few ways to fix this issues and the best way probably depends on how much you weigh.

If you weigh more than 170 pounds, the front springs are most likely too soft and will have a "diving" effect when you ride them (hard braking, over steering in corners) . The stock spring rate is .46, so an upgrade to .48 (obviously the right spring rate depends on how heavy you really are) will help balance the bike out and complement the stiffer rear spring.

If you weigh less than 170 pounds (I weigh 168), the stock front spring rate (.46) is probably close to being right for you. However, the rear shock spring, which is a .54 stock, is too stiff. I swapped out my stock spring for a .51. This should help balance the bike out and prevent the "high" feeling in the rear end. The bike will also break and corner better.

There is a big misconception about going faster and having stiffer suspension. Most people think that the faster they go the stiffer they need to make their suspension. This is partially wrong. The trick to getting your bike to handle bumps and corner right is getting the suspension to work in the right part of the stroke. This is controlled by valving. Once the proper spring rate has been selected for the riders weight, correct valving is what controls the plushness or anti-bottoming effects that we want our suspension to have.

After some testing I will have more posts to follow that talk about the stock valving and some changes that need to be done.

Easy and Economical Fixes

Remove judder spring in clutch. 

How? This is a pretty easy and inexpensive fix that will help prevent your clutch from fading in stock form. Start by disassembling the clutch cover and removing the four clutch springs. Take off the pressure plate and slide out all of the clutch plates and friction disks. The last friction disk you remove is apart of the judder spring. It has a narrower band and has a different friction pattern. Set this disk aside. What remains in the clutch basket are two narrow rings (one is metallic and the other black). Remove these. Replace the judder spring (the last friction disk and two narrow rings) with a standard friction disk. Any year 09-11 will work. Lastly, reassemble the clutch each disk and plate at a time and bolt the four clutch springs back in.

Note: Be careful tightening the clutch spring bolts back in. Honda bolts are known to have some weak bolts, and snapping one off in the clutch basket is the last thing you want to do. Also, add a dab of loctite to those four bolts to prevent them from potentially coming loose. Once assembled, you might have to go back to the clutch perch on the handle bar and adjust the clutch tension to reduce or create some play. Always have a little bit of play in your clutch.

Cost: $6-7

Time: Ten minutes