Author Topic: Big twin rocker shaft retainer bolt - V7 Sport  (Read 2400 times)

Offline Phang

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Big twin rocker shaft retainer bolt - V7 Sport
« on: December 01, 2015, 08:53:34 AM »
I was reading the Guzziology earlier today and got stuck at this particular paragraph.

It contradicts with the parts manual of V7 Sport, the manual printed part# 9805 4314 as M6X12 bolt.

So what do I expect from a presumably unmolested 1973 V7 Sport? 12mm or 14mm?

If the bike has the 12mm bolts, do I replace them to 14mm bolts?

I am confused, please educate me.

Thanks.

Phang







2009 Griso 8V SE Tenni (Green)
2000 V11 Sport (Green)
1973 V7 Sport (Green)

Offline mtiberio

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Re: Big twin rocker shaft retainer bolt - V7 Sport
« Reply #1 on: December 01, 2015, 08:58:00 AM »
do you own a vernier caliper? if so calculate what you need from first principles...
thickness of the washer (when flat)
+
thickness of the rocker tower that the bolt must pass thru
+
no more than the thickness of threads on one side of the hollow rocker pin.

any more than that (a mouthful) is wasted and could block an oil passage.
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Offline Phang

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Re: Big twin rocker shaft retainer bolt - V7 Sport
« Reply #2 on: December 01, 2015, 09:21:13 AM »
do you own a vernier caliper? if so calculate what you need from first principles...
thickness of the washer (when flat)
+
thickness of the rocker tower that the bolt must pass thru
+
no more than the thickness of threads on one side of the hollow rocker pin.

any more than that (a mouthful) is wasted and could block an oil passage.

Thanks, your explanations make sense and easier for me to understand  :thumb:
2009 Griso 8V SE Tenni (Green)
2000 V11 Sport (Green)
1973 V7 Sport (Green)

Online Antietam Classic Cycle

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Re: Big twin rocker shaft retainer bolt - V7 Sport
« Reply #3 on: December 01, 2015, 09:38:14 AM »
Yes, replace the 12 mm "bolts" (hex head cap screws) with 14 mm long bolts. No matter what type of washer you use (schnoor, toothed, wave, split lock), the 14 mm length will engage the rocker pin threads fully, but still won't block the oil passage. Use grade 8.8 bolts.
Charlie

Offline Phang

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Re: Big twin rocker shaft retainer bolt - V7 Sport
« Reply #4 on: December 01, 2015, 09:47:42 AM »
Thanks Charlie, I think I got the picture now.

Only when the bolt is longer than 14mm then it stands a chance of blocking/reducing flow of the oil in passage drilled in the rocker pin?
2009 Griso 8V SE Tenni (Green)
2000 V11 Sport (Green)
1973 V7 Sport (Green)

Online Antietam Classic Cycle

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Re: Big twin rocker shaft retainer bolt - V7 Sport
« Reply #5 on: December 01, 2015, 10:13:37 AM »
Thanks Charlie, I think I got the picture now.

Only when the bolt is longer than 14mm then it stands a chance of blocking/reducing flow of the oil in passage drilled in the rocker pin?

Yes, at 16 mm it will start restricting the flow of oil .
Charlie

Offline Phang

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Re: Big twin rocker shaft retainer bolt - V7 Sport
« Reply #6 on: December 01, 2015, 10:21:35 AM »
I read the same Guzziology paragraph again and it is all making sense now.

Can't learn just by reading a book, you also need the help from teachers and classmates.
2009 Griso 8V SE Tenni (Green)
2000 V11 Sport (Green)
1973 V7 Sport (Green)

Offline rbond

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Re: Big twin rocker shaft retainer bolt - V7 Sport
« Reply #7 on: December 01, 2015, 04:00:17 PM »
And more than a mouthful is NOT wasted. It is just a lot more to enjoy! :grin:
2012 MG V7C
1976 Suzuki GT500A
1978 Suzuki GS400C (long gone)
1973 Suzuki TS 100K (first new bike)
1969 Honda S90 (very first bike)


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