Printable Version | Subscribe | Add to Favourites
New Topic New Poll New Reply
Author: Subject: Rocker thoughts?
PSpirine

posted on 14/7/10 at 08:25 PM Reply With Quote
Rocker thoughts?

I'm close to finalising the geometry of rockers for my Haynes roadster (inboard suspension), but am still undecided as to the best way of attaching them to everything!

One end will activate a standard 9-13" shock, so is a 34mm bracket end.

The other end will be set up to take a spherical rod end with off-the-shelf cone washers either side - any idea what size I should be looking at - M12 beefy enough?

Those are the easy ones.


The last bit, is how do I mount the rocker to the chassis?

I'm trying to keep this relatively low cost, so am trying to avoid 2 bearings pressed into either side of the rocker riding over a shaft mounted on a chassis bracket.

Is there any reason why I can't just make the rocker pivot a 33.7mm opening as per wishbone tubes, and simply fit it with a polybush with crush tube into a standard 44mm bracket?

I was actually considering using bushes on either side of the pushrod as it's riding in a completely vertical plane, but given the cost of bushes, sphericals aren't too far off in terms of cost!


I welcome your thoughts.

View User's Profile View All Posts By User U2U Member
paulf

posted on 14/7/10 at 08:38 PM Reply With Quote
I wouldn't use poly bushes as there is a heavy loading on the rocker bush and it would probably distort and fail fairly quickly.
Needle roller or bronze bushes on a hardened shaft would be the best option. I think some manufacturers used mini or metro rear suspension arm needle rollers.
Paul

View User's Profile View All Posts By User U2U Member
MikeR

posted on 14/7/10 at 09:11 PM Reply With Quote
I heard that as well - but i believe they stopped at some point.
View User's Profile View All Posts By User U2U Member
matt_gsxr

posted on 14/7/10 at 10:38 PM Reply With Quote





J15 and fury solution (both Sylva) and proven to work well.

Matt

View User's Profile Visit User's Homepage View All Posts By User U2U Member
PSpirine

posted on 15/7/10 at 06:38 AM Reply With Quote
Matt, are those just standard poly bushes in the pivot in the lower image?

Cheers,

Pavs

View User's Profile View All Posts By User U2U Member
adithorp

posted on 15/7/10 at 12:40 PM Reply With Quote
quote:
Originally posted by PSpirine
Matt, are those just standard poly bushes in the pivot in the lower image?

Cheers,

Pavs


No, they're nylon bushes, reamed out to be a smug fit on the shaft.
Mini/metro rear arm needle roller bearings have been used as an upgrade, but the small range of movement means they constantly load the same spot on the bearings and can soon fail.

adrian





"A witty saying proves nothing" Voltaire

http://jpsc.org.uk/forum/

View User's Profile View All Posts By User U2U Member
PSpirine

posted on 15/7/10 at 05:26 PM Reply With Quote
Hmm very interesting. So as long as I've got access to a lathe, I can still use standard 44mm crush tubes and suspension brackets, and simply make a very tight fitting nylon bush instead of using standard poly jobbies?

Cheers!

View User's Profile View All Posts By User U2U Member
adithorp

posted on 16/7/10 at 12:30 PM Reply With Quote
The bush is reamed such that it will just hold the (bare) rocker in position but will move easily by hand. The one in the picture has had a grease nipple added. Thats not standard but the pivot tube is mild steel and tends to rust/sieze so it's a common mod'.

adrian





"A witty saying proves nothing" Voltaire

http://jpsc.org.uk/forum/

View User's Profile View All Posts By User U2U Member

New Topic New Poll New Reply


go to top






Website design and SEO by Studio Montage

All content © 2001-16 LocostBuilders. Reproduction prohibited
Opinions expressed in public posts are those of the author and do not necessarily represent
the views of other users or any member of the LocostBuilders team.
Running XMB 1.8 Partagium [© 2002 XMB Group] on Apache under CentOS Linux
Founded, built and operated by ChrisW.