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Discussion Starter #1
1) Know where I could get my hands on one of these popular 175's for my (and your) racing enjoyment ?

2) Where could I find a metric helicoil set so I can replace my 350f Valve cover bolts ? (ie:where do you recommned?)

As always ty, your a gentleman and a scholar... (well scholar anyway;)..

J "not that" D
 

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JD,
I don't have a spare 175 sloper lying around, I've got a rolling chassis (my only spare roller), and a spare engine (my only spare engine). I've got a couple of sloper frames though if you need one.

I've just kept my eye on local want adds and ebay for them. I bet between all us 175 riders we could come up with the parts to build a bike if necessary.

I get my Helicoil kits from McMaster-Carr or MSC.
Try McMaster PN 91732A947 (6mm x 1 repair kit)

or MSC http://www1.mscdirect.com/CGI/NNPDFF?PMPAGE=265

The MSC kits are nice, might as well buy the whole kit that includes an assortment of 6mm inserts, drill bit, installation tool etc..in a neat little box. I always bring my kits with me 6mm, 8mm, and spark plug.

Let me know if you have any trouble ordering them.
JohnnyB
 

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JD
I've got a vert 175 that I'd be willing to sell if it will end up on the track. It's only missing the exhaust. Supposedly ran when I got it but I've never tried to start it.
bfd
 

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"I heard you guys talk about helicoils before, didn't quite get it though. Just googled it, and all I can say is dam nifty. Could have saved me alot of retapping. What kinda torque can those coils handle?"
 

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Ruin,
Typically they can handle more torque than the original thread when used in aluminum.
The reason for this is that first of all the insert is stainless steel...so right from the get go the threads are stronger...plus since you drill the hole out and tap a larger OD hole the outside of the helicoil engages more aluminum than did the original tapped hole so it's harder to pull out.
I've never had a properly installed helicoil fail to accept the specified torque.
JohnnyB
 

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"Any metal-expanding problems?"

"My dad uses a similar thing when fix inlet and outlet port on hydraulic cylinders. Except he machines the the 'tread plugs'"
 

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I don't think I've ever seen any chronic issues with helicoils. They've got the system down pretty pat, they been around for about 30 years now.
I remember back when alloy blocks and cylinderheads were getting popular in racing, we used to helicoil many of the threaded holes before we even used the parts because the helicoils would hold up better under stress than the original tapped aluminum would.

As was being discussed a week or so ago, I just did an "at track" service on an engine I built where I had to tear down the whole top end and helicoil a stripped cylinder stud hole...torqued down just fine...that engine now has two helicoiled cylinder studs and I have no worries as to whether they will hold up or not. I trust them more than I do the 40 year old threaded aluminum holes.

Seriously...helicoils are not considered a "stop gap" fix, they are considered a permanent fix, with characteristics often superior to the original thread. I've seen factory parts come with helicoils installed.
JohnnyB
 

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"I will have too look and see If I cannot find any of those over here."

"Fortunatly, we don't have any thread problems with my block. But if we do pickup any, atleast I now know how to fix it."
 

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JD,
Depends on what size the cover bolts are....I'm guessing they are 6m x 1.0 thread pitch. Next determine how long the inserts need to be...meaning what is the length of the thread in the aluminum on the engine.
Typically honda valve covers, side covers etc use 6mm x 1.0 screws. The proper kit for this screw would be # 00068346 I notice the longest insert it comes with is 12mm...about a half inch...should be long enough...only comes with 6 of each it looks like...so you might want to order more of the inserts that size...depends on how are stripped out, or maybe order some longer inserts. The same tools will work with any length insert of the same thread pitch.
JohnnyB
 
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