VF500 F2 Rear Wheel Impossible!

I agree - from the photos your shock conversion appears to be shorter than the stock shock.

For reference, I have noted that the stock shock is 346mm. Also, on shock conversions - I have a DMr F4i shock - this measures 352mm in length.

Do you have the specs on your F2 shock's length?

 

No I do not. I never thought I should have measured them.

It looks shorter?



If anything, to me, it looks like the same length. (edit....nevermind)

So what do I do now?

 

The preload aduster is the ring at the bottom of the shock. I believe position "1" is the lightest setting.

 

It is a bit hard to tell in the photo - Jamie D. will know, I'm sure - so I don't mean to second guess here.

I doubt he would fabricate something that wasn't correct - so it could be the perspective of the photo that makes it appear shorter.

On a side note - based on going with a 17" wheel conversion the shock should be longer than stock to help get the bike's geometry back in line. I believe that 352mm is about as far as you can take the length.

 

sorry I did not blow up the picture the fist time so I did not see that they were not lined up.
set the sag w/ you on the bike and see what happens.

 

So do I have to turn the ring on the shock to make it stiffer?

Will that increase its length too?

Can this be done with it on the bike?


Jamie. Some advice would be appreciated.

 

yes just turn the ring on the shock and it can be done w/ it on the bike
you want between 25mm-30mm of sag w/ you on the bike.
you should end up w/ 5mm aprox free sag ...that is you off the bike and when you lift the tail section up and take the weight off the shock, it should come up about 5mm
it will not change the lenth of shock.. the lack of sag will increase ride height a bit due to the spring being firmer.

 

The shock I made for you is a bit longer to adjust for the smaller OD tire on the F2 wheel. As mentioned, you can adjust the sag by turning the preload collar on the shock. I'd run 35mm on that bike (the aforementioned numbers are not for your bike). Rider sag is the only important number.

 

So I'm going to have to check the rear sag and adjust accordingly?

I check the sag by measuring the distance between 2 references (1 on swingarm & 1 on tailpiece somewhere) with the rear of the bike suspended.

Then I measure the distance with me on the bike (In full riding position and someone preventing the bike from tipping over) and the difference between the 2 measurements should be around 35mm?

Also to increase preload I turn the collar so the number increases?

 

here these links will help the 1st one also shows alignment
Motorcycle Suspension Guide
opps my comp is f'n up will send you some other links.
I disagree w/ Jamie that 35mm is " the only sag setting " for you bike I prefer 25-30mm for the street. Also if the correct spring was used for your weight you should end up w/ 5mm +/- free sag.
this is how you know it is the correct spring for YOU.

 

Thanks for the link. Similar to what I've read.

Do I have to do anything to the collar to get it to turn? Any tools needed?

I wish I knew I had to adjust the shock before I installed it and took it out of the shop I was storing it in.

 

you need a spanner tool, or you can use channel locks if in a bind.
the preload adj is ment to do on the bike.
oh forgot you have cbr shock, hope you have room to get at it.

 

Well, you really couldn't have set the sag properly before you installed the shock . . . .

One last thing - it can be very dangerous to ride with soft shock. Imagine the shock bottoming out in spirited cornerning, especially with a passenger on board. Ugly! So adjust the preload before you take the bike out again.

 

Minor threadjack -

Jamie, I am running one of your modded F4i shocks on my 1984 VF750F with stock wheel - at least for now. It's a great improvement over the stock POS. What sag do you recommend for my bike?

 

Thanks guys.

I'll get on that.

Unfortunately I have my Forks apart in my basement. Once I have the front all back together I'll start messing with the rear again.

 

Rider sag should be 25-33% of the total rear wheel travel. Based on that, the VF500F should be 29-38mm and your VF750F should be 30-40mm. In both cases I shoot for a nominal 35mm of rider sag. Other comments are based off a different bike and do not apply to the older VF's. You cannot paint the whole picture with a board brush, the devil is in the details and that is why I have carefully considered the facts before stating what sag numbers should be used.

 

Jamie,

May I please get some info on how this shock works? Mainly how I can adjust it?

Is the "collar" with the numbers on it where I'm supposed to adjust it from?

Do I just twist this "collar"?

Do I need to do anything before this "collar" can be twisted?

Which way do I twist it?

There's a little screw with an S and an H to either side of it.....what is that all about?

Thanks in advance.

 

The adjustments are standard CBR, nothing was changed in that regard. Perform the adjustments in this order:

- The large black collar is the spring preload adjustment. The higher number is more preload, you'll need a spanner wrench to adjust it. If you don't already have one, Parts Unlimited has them cheap. I've preset the spring to a value that should be close so if you choose to leave it alone that would be fine.
- The screw near the lower mounting is the rebound adjustment. Turning this screw in (like tightening a bolt) is more rebound damping, out is less.
- The screw on the reservoir is the compression damping adjustment. The direction is the same as above.
- I've also preset both damping adjustments, but feel free to play around with them to suit your riding style.

 

So to fix the problem I am having (as I am told after posting the video) what am I adjusting?

 

Just finished the front forks.

I took everything apart....cleaned everything completely, re-assembled with new Fork seals, dust seals and Circlips. (What a PITA)

Added some 10w Fork oil and put everything back on the bike (Another PITA). Bike feels great up front. Sooooo good.

The previous owner had the bars on much lower.....I put them back up to stock position. Much better.

Now I just have to figure out this rear shock.