Advancer springs

Posted: Wed Mar 15, 2017 12:45 am

Does anyone happen to know if the return springs on the 900f advancer and the 1100 are the same? the springs on my 1100 unit clearly have a spot where they looked to be stretched. I have a 900 unit that has nice springs and would like to swap them.
Thanks.

Posted: Wed Mar 15, 2017 2:43 am

My guess is no they are not. Look at the specs in chapter 1 of the FSMs for the full advance at rpm spec and see they are different...

elsewhere genesound wrote:

I just looked the advance specs up in the Honda Shop Manuals...

cb900 38.5° @ 3200rpm
cb1000 38.5° @ 3300rpm
cb1100 38.5° @ 3500rpm

...

Posted: Wed Mar 15, 2017 10:53 am

I have an 1100 advance unit with the tabs broken off (don't ask, thanks grump). Find that tailpiece and we can work it into the deal. Wink

Posted: Wed Mar 15, 2017 1:22 pm

I would use them until you can find a nice set of 1100f springs, there just isn't that much difference and they are easy to get to. Could be they use the same spring and the weight of the advancer arms is different in which case you are all set.

I see there is a vendor in Japan that sells new aftermarket springs (about $15) but they use the the same spring for the 900f/1100f/1100r so someone is getting slightly different timing.

http://jays-mc.jp/shop/detail.php?pid=83&ct=0&pt=3&

Posted: Wed Mar 15, 2017 1:35 pm

Could the weights be different for the different model advancers?

Posted: Wed Mar 15, 2017 2:06 pm

thx113 wrote:

Could the weights be different for the different model advancers?

That is what I was thinking, J's sells a different spring for the 750f so it must be physically different.

Posted: Wed Mar 15, 2017 2:33 pm

I was thinking the weights would be different. I may try them and see how it runs.

Posted: Wed Mar 15, 2017 5:00 pm

thx113 wrote:

Could the weights be different for the different model advancers?

You're correct, all the weights are different. The 750 has the heaviest weights, the 900 is lighter than the 1100, which is the lighest.

Posted: Wed Mar 15, 2017 8:00 pm

Sonicrete had always stated to use the 900F (438) advancer. He thought that they were the best of the bunch.

CB1100F Joined: May 13, 2005 Posts: 3249 Location: NE OHIO

I thought he said to use the 1100 advancer ???? of course I am old so maybe I don't remember correctly

Posted: Thu Mar 16, 2017 3:45 pm

I have one of both. Guess I can try them both.

Posted: Sun Jun 11, 2017 8:10 pm

BTW, the springs are different, so are the flange bolts that hold it all together. Here's the pics I finally found, 3 months later. Confused

The one on the left is a NOS 900 part with the #10 bolt, the one on the right is from a cb1100, and has a #12 bolt, even harder. You can also see that the 900 spring is longer, probably a different rate as well. (That one 1100 spring in the bottom pic looks a little tweaked)

Posted: Mon Jun 12, 2017 4:11 am

So, assuming the springs stretch or looses some of their tension over time, that would imply the advance is happening sooner than desired - does that make sense?