Author Topic: how to beef up front fork springs on 75 750  (Read 1151 times)

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Offline stickman

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how to beef up front fork springs on 75 750
« on: May 11, 2008, 07:02:19 am »
hi guys,  good morning.  well just had my dry rotted tires replaced with new dunlops on my new to me 75 750k.  the old tires were too scary to get out on the open hiway for an extended run.  did that today and it became apparent quickly that i have front end issues with mild shaking and spongy, soft suspension.  i know i need to install new front fork seals and fluid.  i would also like to do something with the fork springs.  i checked on ebay and could not find any sohc 750 front springs.  any suggestions and where i can find them?  also, what is the recommended method of beefing up the existing stock weakened springs?  seems like i recall something from 30 years ago about adding a spacer at the top but thats about all i can remember.  any guidance would be much appreciated.  next i will deal with my front wheel to check for out of round.  just bought a 4-2 chrome exhaust system off ebay yesterday and am looking forward to replacing the pieced together, modified 4-1 header.  i installed an aftermarket oil cooler yesterday.  i am apparently reliving my past somewhat dressing my bike like i did centuries ago.  oh well, its fun and i enjoy it.  still love that sohc 750 exhaust sound!  enough rambling.  thanks, and have a great day.  Ed, Lenoir, NC
Ed Jones, Lenoir, NC
1971 CB750, 1994 Kaw police bike KZ1000

Offline Lumbee

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Re: how to beef up front fork springs on 75 750
« Reply #1 on: May 11, 2008, 07:33:52 am »
...I want to say progressive makes front springs for the 750s.  Check with u'r local parts house.  New neck bearing will go a long way toward improving u'r front end performance.  So how is the weather in western NC?  I'm moving my wife to Asheville in a couple weeks, and I'll be following as soon as I find work...
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Offline stickman

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Re: how to beef up front fork springs on 75 750
« Reply #2 on: May 11, 2008, 08:06:52 am »
thanks lumbee for the info.  weather here today is wet with light rain but we have been havings lots of sunshine and 70's to low 80 temps.  georgous riding weather.  the blue ridge parkway is a great ride this time of year.  i am 30 minutes from the parkway and it runs right next to asheville.  if you need a riding partner when you get to the area, give me a shout.  my personal bike is a 79 kz1300 and now the 75 750.  i will have one or both ready when you are.  good luck and thanks again.  ed
Ed Jones, Lenoir, NC
1971 CB750, 1994 Kaw police bike KZ1000

Offline mystic_1

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Re: how to beef up front fork springs on 75 750
« Reply #3 on: May 11, 2008, 08:44:18 am »
Hiya Ed.

You can add spacers to the top of the fork springs, between the springs and the fork caps.  I'd start by stacking a few appropriately-sized washers in there, and see how that feels.  Continue to add washers until you get the feel you need.  If you end up using more than a few washers, measure the stack height and make up a permanent spacer from a section of pipe.

cheers
mystic_1
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Offline BobbyR

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Re: how to beef up front fork springs on 75 750
« Reply #4 on: May 11, 2008, 08:44:40 am »
For quick cheap fix you can put a spacer on top of the spring and pre load it somewhat. There is a thread on this somewhere on the site. When you change the fork seals and refill it with fluid, you can also alter the viscosity oil you use to change the damping action.
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Offline Lumbee

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Re: how to beef up front fork springs on 75 750
« Reply #5 on: May 11, 2008, 03:49:29 pm »
...sure thing mystic...we'll have to go bum rush Uncle Ernie (also on the board from A-town) and see what treasures he has hiding in his shop...
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"I'm not a welder, but I play one on HondaChopper.com"