Board logo

GTS Shock absorbers
jonbeedle - 2/3/05 at 09:10 PM

Hi Chaps,

I've just received my shiny new shocks from GTS. Just wondering what mounting bolts to use. If anyone has fitted these can you tell me the bolt size. I have some stainless bolts but I think I will need high tensile ones. I imagine the bolts would need to be a snug fit in the shock mounting. I could probably go out to the garage and have a measure up but I'm laid up with a nasty virus at the moment and it's too cold outside! I'm just about up to the task of bashing the computer keyboard!
Any help always appreciated.
Cheers
Jon


Mark Allanson - 2/3/05 at 09:13 PM

I used 3" x 1/2" UNF equivalent of 8.8 (3 raised bars on the bolt head) and the appropriate nylocks


jonbeedle - 2/3/05 at 09:53 PM

Cheers Mark.


Hellfire - 2/3/05 at 10:17 PM

We used M12 with appropriate Nylok's. Available in various tensile strengths indicated by numbers on the bolt head. Typically 8.8


Mark Allanson - 2/3/05 at 10:31 PM

The eye holes are 1/2"!!!


blueshift - 2/3/05 at 10:55 PM

Doz supplies 1/2" machine screws, I think he called them, with a plain section for the crush tube to sit on. apparently this is a good thing.


Toolbox_USA - 3/3/05 at 07:26 AM

M12 x 7cm, with stainless or zinc washers and Nylocs.

Don't forget copper assembly grease to prevent sieze later...

Stainless will cost double the price of the 12.9 black ones, even by the box. They would be nice looking though!


NS Dev - 3/3/05 at 10:04 AM

I haven't got these shocks, but the holes are usually 1/2" in these things, Mark Allanson would seem to concur this. 12mm if used in 1/2" holes are very likely to come loose due to movement under load.


flak monkey - 3/3/05 at 11:23 AM

The suspension brackets Darren makes have 1/2" holes through them.

http://www.gtscougar.freeserve.co.uk/ubracket2.pdf

The polybush crush tubes have 1/2" holes through them

http://www.cougarracing.fsnet.co.uk/polybush.pdf

So i would think logically that the shocks have 1/2" mounting holes.

0.7mm difference isnt huge, but it will put extra shock loadings on the mounts as the slack is taken up. Would recommend emailing Darren and asking him..but i guess his answer will be 1/2" bolts are the right ones to use!

David


flak monkey - 3/3/05 at 11:25 AM

quote:
Originally posted by Toolbox_USA
M12 x 7cm, with stainless or zinc washers and Nylocs.

Don't forget copper assembly grease to prevent sieze later...

Stainless will cost double the price of the 12.9 black ones, even by the box. They would be nice looking though!


I dont think stainless is recommended for suspension bolts as they dont have a very high tensile strength (much worse than 8.8 steel). You can get special high tensile stainless bolts but i still dont think they match the 8.8 standard. They also cost a fortune...


James - 3/3/05 at 02:28 PM

quote:
Originally posted by Toolbox_USA
<snip>
Don't forget copper assembly grease to prevent sieze later...

Stainless will cost double the price of the 12.9 black ones, even by the box. They would be nice looking though!


Will look lovely- up until your wheel falls off cos the stainless has sheared!
Make sure you use 8.8 or the 12.9 socket caps.

Also, be careful about putting too much copper grease etc. on- apply it after it's all tightened up. Otherwise your just encouraging the nut to come undone- even with nyloc.

Hope that helps,
James


clbarclay - 3/3/05 at 07:10 PM

quote:
Originally posted by flak monkey
The suspension brackets Darren makes have 1/2" holes through them.

http://www.gtscougar.freeserve.co.uk/ubracket2.pdf

The polybush crush tubes have 1/2" holes through them



Thats interesting I've just been making brakets for GTS polybushes, tried a 1/2inch drill bit down the middle of crush tube and it didn't fit. ??
I found a drill bit that did fit in the end, not sure what size it is, my vernier calipers measure in mm and thou but not fractions of an inch. I suspect its some odd imperial bit like a 29/64 or 15/32.
Either way the bit was smaller than 1/2inch and was a perfect fit down the crush tube, probably not the exact same as the bush tube is ment to be as it was a bit to much on the tight side.

[Edited on 3/3/05 by clbarclay]


craig1410 - 3/3/05 at 09:29 PM

Having bought both suspension brackets AND shock absorbers from GTS I can confirm that they are both 1/2". I used 1/2" UNF "S" grade bolts from Namrick with washers and nyloc nuts to secure. These bolts were not expensive and well worth it for peace of mind.

I would agree that it would not be wise to use M12 bolts in a 12.7mm(1/2" ) hole and remember that you will get twice as much movement (ie 1.4mm) as the shock absorber bush will move 0.7mm and the bracket will move 0.7mm, both in relation to the bolt.

Hope this helps,
Craig.

[Edited on 3/3/2005 by craig1410]