'81 Fork Spring Dia

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Ibiro
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'81 Fork Spring Dia

Post by Ibiro »

I live in the twisty's, so every time I ride it's normally sport riding. My exhausts a being ground away and I'm wanting to space the front fork springs by 25-30mm
1"-1 1/4" to get the front up a tad in the corners.
Wanting to get them pre-made, so can just slip them in without waiting for the machine shop.

My question is. What is the standard front fork-spring diameter?

Regards
Daryl

daves79x
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Re: '81 Fork Spring Dia

Post by daves79x »

My question is: what exhaust are you running?

Seriously, if your front fork is set up properly, dragging the stock exhaust is near impossible. A bit heavier springs is probably OK, but you still need a certain amount of sag. If your forks are filled with 10 wt oil to within 6 inches of the tube tops, spring out and fork collapsed, then you'll not be dragging anything but the most ill-designed aftermarket exhaust. And if you are still running the stock rear springer, make sure it hasn't puked all it's oil and your are running max air pressure, or more. Better, get an aftermarket rear shock.

Dave

Ibiro
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Re: '81 Fork Spring Dia

Post by Ibiro »

I’m running 10wt at 6”. Air to max good damping under compression and rebound. All indications are that the oils in suspension is right. Just the first initial fork dive and ride height not good.

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Re: '81 Fork Spring Dia

Post by Larry Zimmer »

What size rear tire? Smaller than stock will have things closer to the ground.
Larry Zimmer
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Ibiro
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Re: '81 Fork Spring Dia

Post by Ibiro »

Everything else is stock. I'm just needing the front with less sag, so I'm wanting to space the fork spring 1".

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SteveG
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Re: '81 Fork Spring Dia

Post by SteveG »

I put the Progressive brand rear shock and Progressive brand fork springs in my 82 CBX and it completely transformed the bike. Well worth the investment.

Fork Springs: https://www.ebay.com/itm/Progressive-Su ... KM&vxp=mtr

Rear Shock: https://www.ebay.com/itm/Progressive-Su ... 2T&vxp=mtr

Steve
82 CBX, 82 CB900F Project, 81 CB900(985)F, 79 CB750(810)F, 06 Wee-Strom

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Re: '81 Fork Spring Dia

Post by steve murdoch icoa #5322 »

Ibiro wrote:Everything else is stock. I'm just needing the front with less sag, so I'm wanting to space the fork spring 1".
If the stock exhaust on a CBX is being "ground away" while riding on the street you should find a race track.
Progressive front springs and an OLD Fox twin clicker on the rear made my '81 a decent back road rider.
'

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Re: '81 Fork Spring Dia

Post by Larry Zimmer »

SteveG wrote:I put the Progressive brand rear shock and Progressive brand fork springs in my 82 CBX and it completely transformed the bike. Well worth the investment.

Fork Springs: https://www.ebay.com/itm/Progressive-Su ... KM&vxp=mtr

Rear Shock: https://www.ebay.com/itm/Progressive-Su ... 2T&vxp=mtr

Steve
Ditto on that, Steve. Made it a totally different bike. On the good side! :P
Larry Zimmer
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Ibiro
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Re: '81 Fork Spring Dia

Post by Ibiro »

Thanks for the input, as always sold experience based advice.
The exhausts are not stock pipes. Upped the fork pressure to 1.1bar and the clearance is way better for the twisty's, no exhaust dragging.

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