Adjusting Front Preload on a CB1100 (Terence O’Keeffe)

[rdprdp01]

Incredibly charismatic and insightful motorcyclist. Hope you enjoy his video as much as I do.

[Cormanus]

Our very own Tev62, unless I'm mistaken.

[pekingduck]

I don't agree with the information given.  He says that preload does not change the spring rate.  This is true on a straight rate spring, but not on progressively wound springs (like on almost all springs now).  

So the the more tightly wound (softer) section of a progressive spring compresses first.  The preload starts compressing this lighter section first, and then the more loosely wound, (heavier) rate sections are then called into play.

Does that sound right? Or am I off base?

[rdprdp01]

PeekingDuck, Although I am knowledgeable about many aspects of motorcycles, maintenance, and riding, I am beyond clueless about forks, suspensions, and preloads. My CB1100EX as it is setup now is perfect for me. I will defer to others to comment on your post.

Here are two things I do know:

1. Mr. O’Keefe has great love for the CB1100 and an enthusiasm that is inspiring.
   
2. The manner in which you expressed your opinion about the content of the video is equally impressive. You voiced concerns in a manner that is both clear and respectful. Thanks for setting the example.
   

I will let others more qualified than me weigh in and then decide if the Thread should remain part of our knowledge base. David

[Cormanus]

This is above my pay grade too. See this article talking about different types of springs. It has some discussion on the effects of preload and, as I read it, conforms that preloading affects both the spring rate and the amount of force necessary to completely compress the spring.

The parts diagram for my 2011 CB1100 would suggest the front springs are either dual rate or progressive.

[dave]

I don't agree with the information given.  He says that preload does not change the spring rate.  This is true on a straight rate spring, but not on progressively wound springs (like on almost all springs now).  

So the the more tightly wound (softer) section of a progressive spring compresses first.  The preload starts compressing this lighter section first, and then the more loosely wound, (heavier) rate sections are then called into play.

Does that sound right? Or am I off base?

Agree.