Threaded rod? Bolts?studs?

GoldenMotor.com

2door

Moderator
Staff member
Sep 15, 2008
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Littleton, Colorado
Where are you planning on using it? Cylinder studs? Make sure you get the right thread. Some engines have course threads in the case, some use fine thread. They might be 1.25 or 1 threads. Discard the kit acorn nuts and replace with hex nuts of the proper thread.

If you're thinking intake and exhaust manifolds, why use studs and nuts? Go with Allen head cap screws instead. Only one set of threads to worry about instead of two.

Tom
 

crassius

Well-Known Member
Sep 30, 2012
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I get 8.8 and 10.9 grades of rod from marshall's h/w - got a store in next town, but avail online too.
 

sbest

Member
Nov 3, 2015
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Nova Scotia
8.8 is standard ISO grade for industry and plenty strong for these engines. 10.9 may be a little brittle for exhaust and motor mounts but fine for head studs. Studs are kinder to aluminum threads than bolts. Twisting a bolt under load into aluminum is very hard on the aluminum threads and will strip them quite quickly. Most hardware store threaded rod and bulk bolts are lower grade, so read the grade. Metric should be 8.8

Steve
 

crassius

Well-Known Member
Sep 30, 2012
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I use the 10.9 on tensioners - when needed, I can squeeze a round chain stay oval shaped without snapping bolt : )
 

wheelbender6

Well-Known Member
Sep 4, 2008
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TX
Threaded rod is good for motor mounts and manifolds. Do NOT use threaded rod for a wheel axle. It will end badly.
 

2door

Moderator
Staff member
Sep 15, 2008
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Littleton, Colorado
The argument against using bolts instead of studs has merit, if, you do a lot of assembly and disassenbly. I try like heck to get things right the first time and seldom have to worry about taking things apart multiple times. I've used Allern head cap screws for intake and exhaust manifolds, engine mounts and in other areas and have accrued thousands of miles on my bikes with no damage to case threads or fastener failure.

Like almost every aspect of motorized bicycle building you have to decide what works for you. Replacing studs with bolts works for me. You'll need to decide if that suggestion is right for you.

Tom
 

Legwon

Member
Mar 2, 2013
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Van bc Canada
If you're thinking intake and exhaust manifolds, why use studs and nuts? Go with Allen head cap screws instead. Only one set of threads to worry about instead of two.
i agree wholeheartedly.
when i was runnin studs, i had them snap every 3-4 weeks.
since running Allen Key Cap Screws, Yes they break... but not often.
over 5000miles, 8months, 3 bolts broken, all easily removed. .wee.