guzziriders.org - moto guzzi forum Homepage
Forum Home Forum Home > Modifications and Restorations > Modifications
  New Posts New Posts RSS Feed - Rear Wheel Offset
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Rear Wheel Offset

 Post Reply Post Reply
Author
Message
INSTG8R View Drop Down
Falcone
Falcone
Avatar

Joined: 31 May 2017
Location: Geraldton
Status: Offline
Points: 24
Post Options Post Options   Thanks (0) Thanks(0)   Quote INSTG8R Quote  Post ReplyReply Direct Link To This Post Topic: Rear Wheel Offset
    Posted: 09 Sep 2019 at 03:57
I have a 99 California EV and want to offset the rear rim 10mm to the right (brake disk) side. Has anyone else attempted this mod? Standard, the rear tyre has 5mm clearance on the drive shaft but 35mm clearance on the swing arm brake side. I want to push the rim over 10mm (offset) so I can fit a 20mm wider tyre on the rear. Re-lacing the original spokes can only get me 3mm as the spokes rest against the hub drive. Before I set to machining the hub I was wondering if anyone has any other suggestions how to gain the 10mm required. Yes I know the tracking from front to back will be out. Don't care! I am building a cafĂ© racer and I want the look of the wider tyre. Thanks in advance. 
INSTG8R
Back to Top
Brian UK View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 13 May 2014
Location: Surrey
Status: Offline
Points: 11560
Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 09 Sep 2019 at 07:41
Most people say that fitting a wider tyre on a Tonti frame screws up the handling. For that reason, I haven't heard of anyone trying what you want to do.
Brian.

Better 5 minutes late in this world than years early in the next.
Back to Top
c13pep View Drop Down
Senior Member
Senior Member
Avatar

Joined: 31 Aug 2017
Location: Doncaster
Status: Offline
Points: 779
Post Options Post Options   Thanks (0) Thanks(0)   Quote c13pep Quote  Post ReplyReply Direct Link To This Post Posted: 09 Sep 2019 at 10:02
Nearly the same but I have had two scooters fail there MOT because of wheel alignment, fortunately that particular tester has closed. When I questioned the decision I was told that he considered it to be a `major` safety issue, my current tester only gives a cursory glance from the rear and does not put the bikes on the lift

CHRIS   
you can`t have any fun in a straight line

Monza
BMW R1150RT
1200 Sport
Back to Top
Dave P. View Drop Down
Senior Member
Senior Member


Joined: 12 Jan 2015
Location: Northants
Status: Offline
Points: 2996
Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 09 Sep 2019 at 10:04
Wider tyre, tracking out, should handle er, interestingly.
Ride Safe !!
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
Back to Top
Barry View Drop Down
Senior Member
Senior Member
Avatar

Joined: 02 Mar 2015
Location: Oxford
Status: Offline
Points: 2183
Post Options Post Options   Thanks (0) Thanks(0)   Quote Barry Quote  Post ReplyReply Direct Link To This Post Posted: 09 Sep 2019 at 10:47
You probably know this, in which case I apologise for stating the obvious, but a wider (rear) tyre for for Guzzis is generally accomodated by putting a 'scallop' into the tube which protects the drive shaft from gearbox to final drive. There's generally clearance on t'other side. Also, I believe (but could be mistaken in that belief) that some Toni swinging arms have more 'clearance' than others.

Back to Top
iansoady View Drop Down
Senior Member
Senior Member
Avatar

Joined: 23 Jul 2017
Location: Birmingham
Status: Offline
Points: 1293
Post Options Post Options   Thanks (0) Thanks(0)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Posted: 09 Sep 2019 at 10:47
In theory the MoT still includes wheel alignment. However, I was told by one tester that there were so many bikes with single sided swinging arms failing - and of course couldn't be corrected - that they'd been advised not to do it. Certainly the place I use now never checks.
Ian
1982 V50
1952 Norton ES2
Back to Top
INSTG8R View Drop Down
Falcone
Falcone
Avatar

Joined: 31 May 2017
Location: Geraldton
Status: Offline
Points: 24
Post Options Post Options   Thanks (0) Thanks(0)   Quote INSTG8R Quote  Post ReplyReply Direct Link To This Post Posted: 09 Sep 2019 at 11:51
Thanks to all who commented.
I am aware of the handling issues that may ensue however it is not being built for the track. Lucky for us in Western Australia we do not have to worry about annual MOT inspections. Bike is already registered so I doubt the local constabulary will know the difference.
 To Barry, Yes the Drive shaft already has a scallop in it. not sure I can scallop it any more before things rub on the inside. When measuring the tyre clearance I was measuring from the side wall to the deepest part of the scallop. Over all width is not the issue, just the wheel sits more to the drive shaft side than the Brake swing arm support. Just need 10mm to achieve desired result. 
INSTG8R
Back to Top
BondEquipe View Drop Down
Senior Member
Senior Member
Avatar

Joined: 10 Dec 2014
Location: Barnacle
Status: Offline
Points: 1353
Post Options Post Options   Thanks (1) Thanks(1)   Quote BondEquipe Quote  Post ReplyReply Direct Link To This Post Posted: 16 Sep 2019 at 11:53
Well it has been done - I've got one in my garage!

It was built by Bruce Rawsthorne (well known Guzzi builder and tuner) and to enable an 1100 Sport rear wheel to fit (to match the 3 spoke Ducati front in USD forks) the frame has been 'sprung' and 20mm width added to the swingarm. This means the wheels are 10mm out of alignment which apparently has never been a problem.  Bike has been on the road and on track.

Personally no idea how it handles as it's still stripped but one day I might find out! 
Stephen
Black & Gold LM2
+ Other Bikes & Projects!
Back to Top
Ben. View Drop Down
Senior Member
Senior Member


Joined: 18 Mar 2015
Location: Lanjaron Spain
Status: Offline
Points: 320
Post Options Post Options   Thanks (1) Thanks(1)   Quote Ben. Quote  Post ReplyReply Direct Link To This Post Posted: 16 Sep 2019 at 13:06
I think we all benefit from people brave enough to push the envelope, so best of luck with the project.
One thing that does puzzle me, is that no cafe racer that I've come across has a rear tyre wider than 3.50 or 4.00 at the most. Were things different in Oz?
Back to Top
Brian UK View Drop Down
Moderator Group
Moderator Group
Avatar

Joined: 13 May 2014
Location: Surrey
Status: Offline
Points: 11560
Post Options Post Options   Thanks (1) Thanks(1)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 16 Sep 2019 at 15:37
It'll be fine so long as you always use a clockwise route. LOL
Brian.

Better 5 minutes late in this world than years early in the next.
Back to Top
nab301 View Drop Down
Senior Member
Senior Member
Avatar

Joined: 29 Oct 2017
Location: Dublin Ireland
Status: Offline
Points: 293
Post Options Post Options   Thanks (1) Thanks(1)   Quote nab301 Quote  Post ReplyReply Direct Link To This Post Posted: 17 Sep 2019 at 19:57
From memory the workshop manual for my BMW has  a tolerance for rear wheel offset ( as apposed to rear wheel misalignment)  of up to 10mm . Could be ABS/ non abs wheel versions using spacers , I'll have to read up on it again...
Nigel
Keep smiling , it makes people wonder what you've been up to!
'19 CB125F,

'18 DL250 SUZUKI V STROM,'99 Bmw R1100S, '03Bullet 65 500, '93 MZ301 Saxon fun (offroad)
Back to Top
INSTG8R View Drop Down
Falcone
Falcone
Avatar

Joined: 31 May 2017
Location: Geraldton
Status: Offline
Points: 24
Post Options Post Options   Thanks (0) Thanks(0)   Quote INSTG8R Quote  Post ReplyReply Direct Link To This Post Posted: 19 Sep 2019 at 03:16
I'm not a purist, just trying to get the right look for my custom build. The tank is off a Suzuki GSX1400 and make the bike look lime a British Bulldog. With theOriginal 7 1/2 inch headlight and tank it is all heads and shoulders so the rear looks a little skinny. With the custom fibre glass tail it realy needs a wider tyre.  
INSTG8R
Back to Top
INSTG8R View Drop Down
Falcone
Falcone
Avatar

Joined: 31 May 2017
Location: Geraldton
Status: Offline
Points: 24
Post Options Post Options   Thanks (0) Thanks(0)   Quote INSTG8R Quote  Post ReplyReply Direct Link To This Post Posted: 19 Sep 2019 at 03:20
Thanks for the feed back. Would love to see the finished product.
INSTG8R
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.02
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.082 seconds.