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On His Lady Vulcan
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Discussion Starter #1
The front fork springs is when??? See here is my delima, I have just recently replaced the front tire with the oversized 110's and ever sense I have had the front end feel a bit looser. Every little bump in the road feels completly different than when I was running the stock tire. Is this normal or should I check out the fork springs? I went through and made sure every nut, bolt and stud was good and tight but it didnt make any differance in the loosness feeling that I have been experiancing. It just seems odd that if the fork springs are shot that it happened at the same time as the tire change. Any Ideas Folks??? Help a brother out.

Peace :beerchug:
 

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Have you ever changed the fluid? Or do either of the tubes leak thru the seals at all?

I don't think the tire size would exaggerate what you feel, but I don't know for sure. Most folks who go up to the 110 seem to like it.
 

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How much air are you running in the tire?
What air pres. if any, do you have in the forks?
Are your bearings in good shape?
Did you torque the axle nut, before you torqued the axle fork clamps?

Like Doug said, with 20k on the bike you might want to change the fork oil.

We're running the same tires and my bike felt, much more stable with the new hides.
 

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On His Lady Vulcan
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Discussion Starter #4 (Edited)
Have you ever changed the fluid? Or do either of the tubes leak thru the seals at all?

I don't think the tire size would exaggerate what you feel, but I don't know for sure. Most folks who go up to the 110 seem to like it.
No, neither fork seals leak. I looked for that thinking the same thing. I will try changing the oil anyways.


How much air are you running in the tire?
What air pres. if any, do you have in the forks?
Are your bearings in good shape?
Did you torque the axle nut, before you torqued the axle fork clamps?

Like Doug said, with 20k on the bike you might want to change the fork oil.

We're running the same tires and my bike felt, much more stable with the new hides.
I am running the front tire at 32psi. max being 40psi. the forks I was running at approx. 30psi (Just released all air in hopes that might be the problem). As for the torquing of the axle nut before the axle clamps I did do it in that order and for the bearings, when I took the tire into have mounted and balanced they spun freely prior with no problems. Thanks for the input you two. I will try changing the fork oil over the weekend for sure. I cant afford to have my bike down long sense it's my only means of transpo.

Peace :beerchug:
 

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Holy ****!!! 7psi is max in the forks. It's know wonder the front end feels weird, with that much pressure, you don't have any front suspension.
 

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On His Lady Vulcan
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Discussion Starter #6
Holy ****!!! 7psi is max in the forks. It's know wonder the front end feels weird, with that much pressure, you don't have any front suspension.
Well hell....I was told just dont go over 36psi. by a trusted Mech... LMAO
 

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From the Kawasaki Service Manual.

Usable range 0-7.1 psi.

Maybe this is where your Mechanic got that number.

There is a caution that states, add air pressure little by little to avoid a rapid increase in air pressure. Air pressure exceeding 36psi may damage the oil seal.
I read this as, the forks hold a small volume of air and if you use an air compressor to inject air into them, it would be easy to exceed 36psi and blow the oil seals. Kawasaki recommends using a hand pump.

There is also a warning. Be sure to adjust the air pressure with in the usable range. Pressure to high can produce a hazardous riding condition.
 

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And...

If my front tire psi is below 34 w/IRC DuoTour (42 max) I get a wandering feeling to the front end. I weigh in at 255 so that might have something to do with it. I changed fork oil to BelRay 10 w last year with a complete flush (total tear down). Works great, but still kinda soft for my weight. Others have suggested pre-loading as 750's don't have air forks.

DT
 

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Early 750's had air forks. I run my forks at 3psi and the front tire at 40psi. The bike is rock soild with this setup. I push the scales at 230#.
You could always add Kawasaki Fork spring seat pn# 44029-1120 and air valve pn#16126-1105 and turn your newer forks into air assist forks. Or drill and tap the spring seat and add a Schraeder valve. Only if your fork seals are in good shape
 

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On His Lady Vulcan
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Discussion Starter #10
I released all air from the forks and now I am off to work so I will have a report on if that was the problem in a couple hours. Thanks for the heads up on the proper air pressure Glen. Yack atcha all laterz.


P.S. I am only 6'0" topping the scale at 180lbs. so with 32psi. and no air in forks well we will see very shortly.


Peace :beerchug:
 

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Measure please

Early 750's had air forks. I run my forks at 3psi and the front tire at 40psi. The bike is rock soild with this setup. I push the scales at 230#.
You could always add Kawasaki Fork spring seat pn# 44029-1120 and air valve pn#16126-1105 and turn your newer forks into air assist forks. Or drill and tap the spring seat and add a Schraeder valve. Only if your fork seals are in good shape
What's the diameter of your forks? I was told the 750's w/o air have a larger tube and a different setup for the caps (mine lock in with a clip, don't think it would hold air.

When you use the term Schraeder valve, do you mean a tank valve? I've done that on several bikes over the years, most resent my 650 Yamaha.

DT
 

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Schrader valves are the standard valves that are used on car and motorcycle tires. Bicycles use Schrader valves on lower pressure tires like those on mountain bikes. The Presta valve is used on high pressure tire applications, like road bikes that run using 110 - 145 PSI.

This is a Shrader valve.

This is a Presta valve.
 

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What's the diameter of your forks? I was told the 750's w/o air have a larger tube and a different setup for the caps (mine lock in with a clip, don't think it would hold air.

When you use the term Schraeder valve, do you mean a tank valve? I've done that on several bikes over the years, most resent my 650 Yamaha.

DT
Both fork tubes are 38mm, both spring seats are held in with a "C" clip.

Thanks Chris for showing the valves.
 
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