Most people over tighten nuts and bolts. Sometimes they really over tighten them. Using a torque wrench would reduce this problem. Practicing with a torque wrench builds muscle memory so you would be more likely to get close to the correct torque when you don’t use a torque wrench. Using a short wrench is another way to reduce the over tighten problem.

But over tight bolts are not all your fault. Mostly, but not all. Bolts get longer when they warm up and shorter when they cool. When your brakes warm up, so do the caliper bolts. The longer the bolt, the more their length can change. Radial mounted calipers have long bolts that are warmed by the hot calipers.

When you change your wheels at the track, you tighten the warm caliper bolts. When these bolts cool they get shorter and tighter.

I warmed one of these bolts up, it’s length increased from 71.34 mm cold to 71.53 mm warm. I installed this warm bolt into it’s caliper and torqued it to 12 foot pounds. After it cooled, I needed 24 ft/lbs of torque to remove it.

You are already aware that hot things expand and cold things contract. Put these tools and this knowledge to good use.

MG takes photo’s too.  He just posted up his stuff from WERA West @ Vegas.  You can buy them here:

http://www.motorbikeroadracing.smugmug.com/

You have to copy and paste, I don’t have links set up.

This Saturday at Douglas Motorcycles I’ll be giving free Suspension Seminars, adjusting suspension and making podcasts with MG. Details on Face Book here:

https://www.facebook.com/events/1709565295952562/

Suspension Seminars at 11:30 am, 1:30 pm & 3 pm.

During the past five years, Lindemann Engineering’s Ed Sorbo has been working on a new formula to more accurately calculate the correct spring rate and pre-load for a given rider and motorcycle weight.

Sorbo first realized there could be a better way after analyzing Jim Lindemann’s notes on spring dimensions and more specifically the relationship between a spring’s spiral shape, circumference and diameter.

This led Sorbo to study potential applications for the famous formula Pi, the ratio of a circle’s circumference to its diameter, 3.14 etc., in the context of motorcycle suspension behavior.

The results of Sorbo’s initial theoretical calculations appeared to be simply random numbers, like the cosmic microwave background radiation (CMB) left over from the Big Bang. CMB is so random that it is used to encrypt secure messages.

In a mind-bending eureka moment, Sorbo realized that the CMB is Pi. The reason no one noticed before is simply that we can’t yet see back to the very beginning of the Big Bang to see the three that comes before the decimal point.

Sadly, this discovery of the answer to life, the universe and everything has not led to a better spring rate calculation, or anything else useful, but pure research is like that sometimes. Surely someone will eventually find a way to utilize the knowledge that Pi surrounds us and penetrates us; it binds the galaxy together.

We all know that the Answer to the Ultimate Question of Life, The Universe, and Everything is 42. If you don’t, please read all the books you can find by the eminent British scientist, Douglas Adams.

Photo Caption: Ed Sorbo has been through the desert on a scooter with no springs.

The five mph pit speed limit does not mean someone is waiting with a radar gun to bust you. Rather, it is a way for each of us to show the others that we understand the responsibility to each other that we have all accepted. By riding in first gear with both hands on the bars we are showing that we know what to do under a red flag, that we checked our grid spot before heading out to race and that we have read the rule book.

A long time ago I had a cable driven tach that failed. Of course it did not just break all the way, it would only go to about ¾ of red line. The problem never showed itself on the street. I don’t remember if it caused a problem at the track but I do remember revving it up in the shop till the valves floated, this was before rev limiters.

When Seed told me his ’91 RGV250 was cutting out on top and that he had good plugs and caps, a common problem on TZ250’s. I told him to check his tach and as he had a good spare this was easy to do. Problem solved.

Suspension expert, check.
Able to remember stuff learned the hard way, check.
Lindemann Engineering, not just a great name, a way of thinking.