Koni shock rebuild

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Tom H Ca
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Re: Koni shock rebuild

Post by Tom H Ca »

The 7610's I believe are all the same basically the same inside. When I did my shocks, I bought a seal kit on fleabay. The rest of the parts looked fine.

The link I posted has a link to a step by step rebuild. It's not hard except for the gland nut. If you have a dirt bike shop near by, they may have a spring compressor and the tool for the nut. Do the rest yourself and bring back to tighten the nut and install the spring. Takes about 1/2 hour each shock.

Be sure to read the part about the hole that squirts oil all over your shirt :o

Tom
'73 R75/5
'70 Guzzi Ambo 750
'72 Guzzi Eldo 850
'04 Guzzi California EVT
'07 HD Dyna Street Bob
'53 Triumph 6T (To be restored one day)

Tom
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Zombie Master
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Re: Koni shock rebuild

Post by Zombie Master »

With damping adjust ability on these units, considering the considerable weight of the drive line on these shaft drive bikes . I'm wondering if going up to 7.5 weight might give better control. My research shows that suspension fluids can vary wildly in terms of consistency of viscosity. My local dealer has a synthetic one rated from 2.5 - 5. WTF? Yet another good problem!
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PAS
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Re: Koni shock rebuild

Post by PAS »

Keep in mind you really cant go by viscosity numbers. One brands 5W may be another brands 10W. Look into viscosity index numbers.
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Re: Koni shock rebuild

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PAS wrote: Wed Mar 31, 2021 6:06 pm Keep in mind you really cant go by viscosity numbers. One brands 5W may be another brands 10W. Look into viscosity index numbers.
"Consumers like to shop for oil by weight. So, the motorcycle industry took the SSU/VI measurement and converted it to weights based on the same scale used by the SAE. But since the SAE weight schedule is so widely incremented, two cans of fork oil with different SSU viscosities of 80 and 100 can both be listed as a 5 weight (5wt). Yes, it is confusing!" WTF! :evil:
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Zombie Master
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Re: Koni shock rebuild

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Rob Frankham
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Re: Koni shock rebuild

Post by Rob Frankham »

Interestinglt, the 'W' in he SAE rating of oils doesn't stand for 'weight' at all, it stands for 'winter' and relates to the viscosity at 0 degrees centigrade. It says absolutely nothing about the viscosity at other temperatures.
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Zombie Master
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Re: Koni shock rebuild

Post by Zombie Master »

I also find it interesting that some companies have different spec for fork and shock oil. Some don't.
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Kurt in S.A.
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Re: Koni shock rebuild

Post by Kurt in S.A. »

For engine oils, the viscosity is tested at 100 degC. I tested a number of 20w50 oils 8 years ago and typically all of the viscosity tests showed the cSt (centistokes) at 100 degC to be within a couple of points or 20. That seems to be the case with the suspension fluids based upon the link...at 100 degC, it's visible that the number is pretty close to the "rating" of the fluid. If it is well below the "w" number then it's likely an inferior oil. If it is above the "w" number, then that means it can give up some of its viscosity due to wear/tear and still fall within the "w" rating.

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Rob Frankham
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Re: Koni shock rebuild

Post by Rob Frankham »

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Re: Koni shock rebuild

Post by Zombie Master »

So there is no standardization for suspension fluids. 5 wt in one brand could be another brand’s 10 wt.

They only use the 5 wt rating (which is not SAE), is to give the consumer some idea, but these relative ratings are only useful within brand lines.

Smaller differentials in viscosity at tested temperatures indicate a more stable fluid.

Fork oil should be a different product than shock oil due to the hotter temperatures and lower fluid volumes. I ended up ordering Red Line lightweight 5wt fluid ester based 100% synthetic, and very high viscosity index. It was recommended by Ikon. It was Interesting to find out that Bel Ray does not make a shock fluid these days. :|
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