Hi all, I'm new to the forum and would like a bit of help with a problem I'm having.
I have a 1990 3cv and I bought some shorter dogbones to raise the rear of the bike but the swingarm won't drop low enough to accommodate them. The very bottom of the spring is in contact with the pivoting crossmember of the swingarm.
I need maybe 5mm to get the bolts through so was thinking I might grind a half moon on the swingarm and maybe a tiny flat on the shock. Has anyone else had this problem and how was it resolved?
Many thanks in advance for any info.
Andy
Quote from: lordsexton on May 11, 2017, 06:44:01 AM
Hi all, I'm new to the forum and would like a bit of help with a problem I'm having.
I have a 1990 3cv and I bought some shorter dogbones to raise the rear of the bike but the swingarm won't drop low enough to accommodate them. The very bottom of the spring is in contact with the pivoting crossmember of the swingarm.
I need maybe 5mm to get the bolts through so was thinking I might grind a half moon on the swingarm and maybe a tiny flat on the shock. how was it resolved? Has anyone else had this problem
Many thanks in advance for any info.
Andy
I don't believe so, unless the new dogbones are excessively short. Plenty of folks here with shortened links but I don't recall this problem being raised.
Noel
I seem to recall fabricating mine to 115mm center-to-center which worked out to a very nice ride height. Never had any clearance issues.
When I installed the RPM shock on my '89, I ran into a similar issue. To get the ride height that I wanted, the shock spring contacted the swing arm cross member. I made a set of dog bones that give the spring about 1/8" clearance to the swing arm cross member.
As for cutting away material, I would definitely not remove any material from the shock spring.
Fred
Thanks fo the replies, mine are only 100mm centre to centre. I'm wondering if I've been sold a pup as far as my dogbones are concerned so to speak. They were from Lust Racing over here in the UK.
Welcome Andy :drinks:
Here's a tip I learned from the guys here on the forum.
When your bike is on the center stand, you want to be able to rotate the back tire to lube the chain.
Therefore, to get an idea where those bones will put your back end, put your bike on the center stand, disconnect the linkage to drop the back tire on the ground. Now slip a piece of 1/2" plywood under your back tire. Now measure the center to center of the dog bone thru bolts. That's your measurement.
I suggest a 1/2" clearance only because tires, even though the same size listed, have variances in height (and width) so you should be safe with a 1/2" clearance.
I made a mistake several years ago, I used 1/4" clearance, with a worn back tire.
When I put the new tire on, I could not spin the back tire.
Cheers lad! Pat
I have a works shock on my 89 came with the bike. The spring is slightly bigger around and hits as soon as I release the stock
If I recall correctly the standard eye to eye measurement is 12.5cm, and shortening by just 1cm to 11.5 eye to eye works great as has been mentioned. With the GSXR wheel mod and new 180/55 tyre I have around 1/4" clearance to the ground while on the centrestand. An added benefit it makes it really easy to get the bike onto the centrestand now, :good2:
Quote from: giantkiller on May 11, 2017, 05:27:33 PM
I have a works shock on my 89 came with the bike. The spring is slightly bigger around and hits as soon as I release the stock dogs woof woof
Quote from: Pat Conlon on May 11, 2017, 04:10:47 PM
Welcome Andy :drinks:
Here's a tip I learned from the guys here on the forum.
When your bike is on the center stand, you want to be able to rotate the back tire to lube the chain.
Therefore, to get an idea where those bones will put your back end, put your bike on the center stand, disconnect the linkage to drop the back tire on the ground. Now slip a piece of 1/2" plywood under your back tire. Now measure the center to center of the dog bone thru bolts. That's your measurement.
I suggest a 1/2" clearance only because tires, even though the same size listed, have variances in height (and width) so you should be safe with a 1/2" clearance.
I made a mistake several years ago, I used 1/4" clearance, with a worn back tire.
When I put the new tire on, I could not spin the back tire.
Cheers lad! Pat
Hi Pat, seems like sound advice if you`re making your own up. Something I may have to do. Got to try and get my 50 quid back now.
Quote from: X-Ray on May 11, 2017, 05:48:30 PM
If I recall correctly the standard eye to eye measurement is 12.5cm, and shortening by just 1cm to 11.5 eye to eye works great as has been mentioned. With the GSXR wheel mod and new 180/55 tyre I have around 1/4" clearance to the ground while on the centrestand. An added benefit it makes it really easy to get the bike onto the centrestand now, :good2:
That being the case, mine would be 2.5 cm shorter than standard, a bit too much maybe.
Quote from: X-Ray on May 11, 2017, 05:48:30 PM
If I recall correctly the standard eye to eye measurement is 12.5cm, and shortening by just 1cm to 11.5 eye to eye works great as has been mentioned. With the GSXR wheel mod and new 180/55 tyre I have around 1/4" clearance to the ground while on the centrestand. An added benefit it makes it really easy to get the bike onto the centrestand now, :good2:
I can confirm this. I have this exact modification.
Quote from: ZOA NOM on May 12, 2017, 08:25:36 AM
Quote from: X-Ray on May 11, 2017, 05:48:30 PM
If I recall correctly the standard eye to eye measurement is 12.5cm, and shortening by just 1cm to 11.5 eye to eye works great as has been mentioned. With the GSXR wheel mod and new 180/55 tyre I have around 1/4" clearance to the ground while on the centrestand. An added benefit it makes it really easy to get the bike onto the centrestand now, :good2:
I can confirm this. I have this exact modification.
Me too ... :good2: ..tho at present I have a gsxr 1100 4.5'' wheel with a 150/70/17 rear tyre and the wheel doesnt turn cos the tyre touches the ground ..I dare say with a lower profile tyre it would turn ..and yeah its soooo easy to put up on the centre stand .. the handling is so sweet with 17'' rear... also have a fzr 750 genesis front wheel to fit soon :)