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Progressive springs installation: Please advise

Trionda

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I am in the process of doing a complete head-to-toe tune up of a good mate's Bitza CB750 (let's just call it a 1977K model), and he's been very good about ordering the parts I request, as I need them.
After getting the bike running again, and having a chance to give it a good shakedown run, I noticed a lot of dive in the front end, and upon tearing into the tubes, I noticed the bike still had its original springs, and asked that he order Progressive springs.
He bought them (new) from some supply warehouse, and there are no directions in the box. None at all.

The springs are a tad bit shorter than the stock springs, and have nylon spacers and washers included in the kit.

My questions are these:
What order are these bits to be installed in, and do I install the tight side of the coils face down or up?

Thank you all.
 
Of course you're right...
Just thought this might be a common switch over, and I'd get a quick answer.
Nevertheless, thanks for the info.

Judging by the pictures in the link you provided, it would appear that the washers go in, then the nylon spacers, and then the springs--tight wound side down.
I won't accept that as correct until I verify it, but it stands to reason that Progressive would not take photos of an incorrectly assembled set-up.

Regards, and thanks again-
 
I don't think it would matter which way the springs go. Would it?

I'm thinking it absolutely would.
I hear you, though. The spring compresses, and at a certain point it acts similarly, regardless it's position, but one has to take into consideration momentum, inertia, front end-dive, and whether mounting the spring upside down will negatively impact the optimal characteristics designed into the spring.
Regards-
 
I'm not an engineer, but I just can't see how it would matter. The spring doesn't know if it's upside down and it compresses the same either way. It only sees the force from each end of the spring right?
 
purely theoretical here,, if the tight side of the spring is down and that is the end to be impacted first on a bump,wouldn't that be where the less dive comes into play?
 
I say no. The spring will compress the same. It shouldn't matter from which side of the spring it is being compressed from. It's not as if the coils on the side of the spring you push on compress first.
 
I say no. The spring will compress the same. It shouldn't matter from which side of the spring it is being compressed from. It's not as if the coils on the side of the spring you push on compress first.

Dunno...

It may not amount to a hill of beans how the spring is mounted, and as you can see, I still have not been able to pull myself away from work to find out.

I'll find out soon.
 
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