Disc Brake from left to right side

Status
Not open for further replies.

hillbone

VIP MEMBER
Joined
Aug 24, 2009
Messages
151
Country flag
gidday . are there any adverse effects from swapping my Mk3 front disc from the left side to the right side. The caliper would be trailing rather than leading.

i will need to have the tyre reversed as well. it is a twin pot Brembo on a larger floating disc set up from colorado Norton works. My reasoning is my new braided brake line won't reach the wider bars I prefer and that problem will be solved by having the caliper on the same side as the master cylinder and I think it will look better behind the axle anyway. I have the smaller colorado guard with no side stays to interfere with the caliper. Cheers
 

dero

VIP MEMBER
Joined
Jan 22, 2010
Messages
223
Country flag
I have had my disc on the RHS Mk2 850 for many years Recently changed to CNW brembo , never had any problem with either brake. If anything it seemed to cure low speed wobble slightly.
By the way the brembo is excelent
 
Joined
Jan 31, 2010
Messages
2,949
Country flag
Can't imagine it wouldn't work fine; however, according to the Norton Owners Club Service Notes, the original right side position was changed to the left by the factory to eliminate the fact that Commado's pulled to the left...Yeah, beat's me. But here's the quote from the manual:

"You should all know the story of the front brake, position---originally fitted behind the right hand leg. For some exceedingly technical reason this caused all the bikes to pull to the left, and made most of them so bad that you couldn't steer the machine hands-off. Nortons which wouldn't steer hands off! And no-one complained. Well, actually, about a dozen people did, but there wasn't anything that could be done about it. Anyway, later it was found that if you take the forks out of the yokes and swap them over the brake finishes up in front of the left hand leg and the machine then steers O.K. No, I can't explain it either. This is not the safest thing to do because there is a grave danger (that is, a danger which might lead to the grave) that the bearing
locking ring will unscrew if the rotation of the wheel is reversed. Do it by all means, but make up some way of securely locking the bearing ring."
 

cNw

VIP MEMBER
Joined
Apr 16, 2009
Messages
464
Country flag
Hey,

There is absolutely no concern moving the disc brake to the right side, where it belongs. As most of you know, the MKIII lower fork legs are actually -74 and earlier models just turned backwards. By running your disc on the right you will also now have the caliper 'before' the fork leg which is something many brake manufacturers prefer. The Brembo, due to the differential bore caliper works better mounted on the right side. It works great mounted on the left as well but ultimately its designed to be mounted on the right.

You dont have to worry about anything backing out as far as bearing retainers since the MKIII hub uses a circlip instead on a threaded lockring.

Your cable routing will be cleaner and more direct and since you are running a smaller fender you dont have to worry about the lower fender stay.

We have actually never built a MKIII model with the brake on the left side. All of them have been converted to right side mount.

Works great and looks great.

Get a hold of me in the shop if you have any questions in regards to the swap.

Thanks

Matt / Colorado Norton Works
 

hillbone

VIP MEMBER
Joined
Aug 24, 2009
Messages
151
Country flag
Good news from all. Matt, i have finally got the bike on the road. CNW Disc set up works a treat, front and rear. Will post pictures to you. Cosentino and Dave Taylor gear transforms the handling to a completely different positive feel. Cheers
 
Joined
Feb 13, 2010
Messages
38
Hello All

This is my first post on this forum, so I please bear with me if it doesn't come out right....

I have a stock '74 build 850 MKIIa which pulls to the left. I've been trying to cure this for four years: I've managed some improvement but it's still not right.

I've seen a few comments in various places that the brake on the right fork leg is the cause, but never any explanation that I can accept. However, today I've had a "Eureka! moment".....

As part of my winter maintenance, I've got the bike set up on a stand with the steering head vertical to check the alignments. I took the front wheel out, and the steering promptly fell onto full right lock. I straightened it again, but as soon as I let go the same happened. My first thought was that the frame wasn't vertical or that the cables were binding, but neither was the case. I then realised that the mass of the caliper and master cylinder were pulling the steering over, and that a pull of around half a pound was needed on the 'bar-end to hold the steering in the straight-ahead position, even without the wheel. Add on the mass of the disc and it's clear that significant forces are acting on the steering, even without input from the rider.

I reckon this is a feasible explanation of why the bike needs pressure on the 'bars to go straight and why it pulls to the left hands-off (counter-steering principle - to turn left, pressure 'bars to the right). Why swapping the disc & caliper to the left fork leg should be a cure, I'm not sure...... Unless the mass of the brake on the left is then balanced by the master cylinder on the right?

Does this sound reasonable, or am I just trying to convince myself that I'll never fix the problem, so should learn to accept it?

I look forward to your views

Ride safe

Mitch
 
Joined
Jul 4, 2009
Messages
372
Country flag
I think you might be onto something there Mitch, I moved my caliper over from right to left years ago, ('73 Interstate) and it doesn't pull. I never understood why but i'd never thought about the countersteering connection, I think that could be it!
regards,
Dave.
 
Joined
Jan 31, 2010
Messages
2,949
Country flag
Makes sense to me! I guess the only "issue" (is it real or not) is that instead of the caliper "pushing" into the fork slider, it is "pulling" away from it. Logically it would not seem nearly as strong since all the force would be trying to rip the AL mounting tabs from the slider. But since the factory went to that option in the Mk III, I guess we can "assume" it's OK...or not?
 
Joined
Aug 26, 2009
Messages
280
Country flag
CNW said:
Hey,

There is absolutely no concern moving the disc brake to the right side, where it belongs. As most of you know, the MKIII lower fork legs are actually -74 and earlier models just turned backwards. By running your disc on the right you will also now have the caliper 'before' the fork leg which is something many brake manufacturers prefer. The Brembo, due to the differential bore caliper works better mounted on the right side. It works great mounted on the left as well but ultimately its designed to be mounted on the right.

You dont have to worry about anything backing out as far as bearing retainers since the MKIII hub uses a circlip instead on a threaded lockring.

Your cable routing will be cleaner and more direct and since you are running a smaller fender you dont have to worry about the lower fender stay.

We have actually never built a MKIII model with the brake on the left side. All of them have been converted to right side mount.

Works great and looks great.

Get a hold of me in the shop if you have any questions in regards to the swap.

Thanks

Matt / Colorado Norton Works


Come on Matt, you know I bought your front and rear systems and I left my MK III with the front caliper on the left as God intended for Mark III's. With both calipers on the right the bike would tend to veer to the right on braking wouldn't it. :D By the way, Matt's brakes systems are the absolute best engineered, in my opinion.
 
Joined
Oct 23, 2009
Messages
159
Country flag
The pull to the left was an "engineered in" safety feature developed by those good people at Norton for those of us that drive on the "Correct" side of the road (left), & was intended to help us to avoid straying into the path of oncoming traffic. This safety feature had of course to be removed on the MK111 as it was aimed at the export market where they drive on the wrong side of the road anyway, & could have had disasterous results.
Terry
 
Joined
Dec 19, 2004
Messages
413
Country flag
Greetings,
On Thursday June 21, 2007 I posted my experience with swapping the fork legs, the post was titled "Pull To The Left Cured". I drove my bike with that pull the left for 6 years and it always seemed like a thorn in my side for an otherwise great bike. The fork swap cured it, I only wish I had found out about it sooner.
GB
 
Joined
Apr 15, 2009
Messages
11,442
Country flag
geo46er said:
Greetings,
On Thursday June 21, 2007 I posted my experience with swapping the fork legs, the post was titled "Pull To The Left Cured". I drove my bike with that pull the left for 6 years and it always seemed like a thorn in my side for an otherwise great bike. The fork swap cured it, I only wish I had found out about it sooner.
GB

pull-the-left-cured-t1907.html
 

cNw

VIP MEMBER
Joined
Apr 16, 2009
Messages
464
Country flag
You can certainly mount our Brembo kit on either side and it will perform extremely well. Personally I just have always liked the way it works and looks when mounted on the right. We have however many customers that have purchased the system, and are using the left side mount as on the original MKIII.

As far as pulling to the right when both discs are mounted on the right, I dont think that is an issue. There are some production bikes that have the discs mounted on the same side and this have not caused any problems. I have also talked to both Brembo and PM (Perfomance Machine) about this set-up and neither of them were concerned about it.

Matt
 
Joined
Oct 12, 2007
Messages
2,904
Country flag
Re: Pull to the left cured !

I think there's an inherent misalignment in all Commandos. When you have a bike that's not built around centerline, it's near impossible for it to track with no input from the handle bars. I just consider it part of the Norton "charm". The Commando has wheel offsets, cradle/swing arm offsets and who knows what else. I do know my BMWs tracked straight with no hands. If I were to sraighten out a Commando here's what I'd do.

(message moved - as it was originally posted on the old 2007 thread - L.A.B.)
 
Joined
Jan 31, 2010
Messages
2,949
Country flag
Well, before I'd even consider all that work on a Commando I'd dump it and buy a new Ducati. :)
 
Joined
Oct 12, 2007
Messages
2,904
Country flag
Well, before I'd even consider all that work on a Commando I'd dump it and buy a new Ducati.

Now, there's a smart man.

In fact, I may just do that. Those new Monsters look pretty intriguing. I'm sixty-five and don't find wrenching as much fun as I used to. Riding is what I want to do now.
 
Joined
Aug 26, 2009
Messages
280
Country flag
"As far as pulling to the right when both discs are mounted on the right, I dont think that is an issue."


I was kidding!!!!!!!!!!!
 
Joined
May 19, 2009
Messages
644
MexicoMike said:
Well, before I'd even consider all that work on a Commando I'd dump it and buy a new Ducati. :)
When guys our age ride new Ducatis they look like trophy wives. It ain't dignified. It's nice to have a mistress with red hair and long legs, but you don't need to dump the wife. And don't forget,the upkeep on both mistresses and Ducatis is way high.
Stephan's opus is a little misguided and wayy too long.
 
Status
Not open for further replies.
Top