Topic: 750 swing arm in 500 frame

[Bluegreen]

Looking for some input here. Yesterday I was at a garage sale and I picked up a 750 swing arm for $10. It looked beefier than my 500 swing arm and I have heard they swap right in. My thoughts are

a) Looks stiffer = good
b) 1" or so shorter than my stock arm  = shorter wheelbase = flicks over faster = good

Does this make sense?

Thanks for your thoughts.

[Retro Rocket]

Your bike will be more stable with the longer stock arm, lots of racers actually fit longer arms to make the bikes handle better, it may be a bit stronger but not necessarily an upgrade for the 500-550.....

[voxonda]

+1,

Found out that the 750 is much more stable with a longer swingarm. To have it 'flick' over faster, you could run longer shocks or use other triples to change the off-set.

rob

[turboguzzi]

i am going to offer you an opposite view coming form someone who raced a 500 rather than a 750,

many people in the Italian series (and we have plenty 500/4 here) go for the shorter 750 arm as it indeed quickens steering and I have not seen any instability problems with the shorter arm

so how do your tracks look like? are they mostly high speed bends or the shorter/slower type? would choose the arm according to that, but you will not go wrong with the 750 arm.

TG

[voxonda]

One cannot compare the 500 with the 750. Still believe the influence of the swing on quicker steering is not as big as adapting the front. I like a stable bike, who needs some input to steer in.

Rob

[turboguzzi]

One cannot compare the 500 with the 750. Still believe the influence of the swing on quicker steering is not as big as adapting the front. I like a stable bike, who needs some input to steer in.

Rob

Hi Rob,

it sounded to me like BG wanted to fit that 750 arm to a 500 rather than back to a 750 .... but maybe i got it wrong

how is your son doing?

TG

[voxonda]

Hey TG,

You just might be right. Looks like BG wants a 750 sa in a 500.....sorry misread it.

Bryan is doing reasonable well, tomorrow the stitches are going to be removed and will get new stretchbandage. All is looking good, thanks.

rob

[Howell]

We changed on our Cb500 racer a 750 short K arm into the 2cm longer F2 swingarm  and now the bike is very stable.

[Bluegreen]

Hmmmm, what to do... The bike handles very good at this point, longer progressives in the back already,steering damper, front end totaly rebuilt, progressive springs there too and lowered 1/2" in the front. But like everbody else, always looking for just a little bit better. I may have a really good balance but I guess there's no harm in giving it a try.

Now if only I extra chain kicking around...

Oh and yes, it's a 750 swingarm going into a 500 frame.

Thanks for the input all.

[Howell]

We changed on our Cb500 racer a 750 short K arm into the 2cm longer F2 swingarm  and now the bike is very stable.

The short swingarm is for sale.

[Kemp]

I'm going to try the shorter (1") 750 swingarm as well in a CB550. Looking for the same improvements you speak of, stiffer arm with quicker steering.

 I also have a CB500 and used progressive springs in the front and progressive shocks in the rear (13 1/2"). I have instability (wobbles) but had the same issue with stock shocks. Really like the way the bike turns with the longer shocks and the front end feel and dive is definitely better with progressive springs.

The very best front fork response I've found with these CB500/550s is using stock springs and a cartridge emulator. Gives the springs an inch of preload which is nice especially if they are a bit tired but really improves the dampening to an almost modern sport bike feel.

[turboguzzi]

I'm going to try the shorter (1") 750 swingarm as well in a CB550. Looking for the same improvements you speak of, stiffer arm with quicker steering.

 I also have a CB500 and used progressive springs in the front and progressive shocks in the rear (13 1/2"). I have instability (wobbles) but had the same issue with stock shocks. Really like the way the bike turns with the longer shocks and the front end feel and dive is definitely better with progressive springs.

The very best front fork response I've found with these CB500/550s is using stock springs and a cartridge emulator. Gives the springs an inch of preload which is nice especially if they are a bit tired but really improves the dampening to an almost modern sport bike feel.

you need smaller offset triples to restore the lost trail because of the geometry change,