R6 Brake Upgrade Issue

[bobber]

I was never impressed with the braking on my 89 Venture so after absorbing a little info from some of the very knowledgeable folks on this website, I gathered all the necessary parts and ventured forth (no pun intended). The blue dot calipers I acquired were off of an 2004 R6 with the appropriate mounting needed for the Venture. I slipped the old calipers off without unhooking the brake lines and tried the new calipers for fit before installing the new brake pads. The R6 caliper mounts slightly off center and the rotor rubs on the caliper casting. The rotor is true as the casting remains in contact as I turn the wheel. I noted that the cut out in the caliper casting (allows the rotor to pass through) was smaller than the original caliper. I measured the thickness of the rotor at 7mm and the cut out at 9mm. Not much room for error. Makes me wonder if I have the right R6 caliper. I have supplied some photos of the R6 caliper and I have a few questions.

Is this the correct caliper for the conversion? If it is the correct caliper why would the rotor rub on the casting? Any assistance would be much appreciated.

[VanRiver]

Hi @bobber.....I have put R6 brakes on three of my MKII ventures and never had a problem like you are describing (both Blue dot and Gold dot calibers front and rear). They should be plug and play with no alignment or fit issues. Here are a few pictures from one of my bikes showing alignment as well as a comparison of a R6 caliber I had on my bench compared with a stock Venture one to compare.....the gap looks pretty well the same size to me....but I didn't measure exactly.

 

 

I have a few questions for you:

 

1. Is your rotor (Disc) original stock yamaha or after market?

2. Silly question but I need to ask.....any fork damage that could have changed the geometry of how the calliper is fitting?

[bobber]

Thanks for the reply and photos. The rotor is stock Yamaha and the thought of fork damage did cross my mind. I have a 93 Venture that I can try the R6 caliper on and see if I get the same fitting issues. It seems that I have the correct R6 caliper unless someone chimes in to the contrary. Let you know how it goes.

[Trader]

You didn't mention front or rear being the problem.

If it is the rear is it possible that the alignment is off because you installed the spacing washer on the wrong side?

That seems to be a common mistake.

[bobber]

The issue is with left side front. I reinstalled the original caliper and inspected it to see if the rotor was centered in the slot in the caliper casting. It also seems to be slightly off center but not affected as the slot in the casting is 2mm wider than the R6 caliper. I installed the R6 caliper on my 93 and it fits but just barely (1mm clearance on both sides). I guess that means I have to find 1mm clearance somewhere for the R6 caliper to work on my 89. Not sure where to start.

[syscrusher]

You didn't mention front or rear being the problem.

If it is the rear is it possible that the alignment is off because you installed the spacing washer on the wrong side?

That seems to be a common mistake.

 

Hey! Can you put a different caliper on the rear? I hadn't heard of anyone doing that but if it's a possibility count me in!

 

Can you tell me what is needed or point me to a thread on the subject?

[VanRiver]

Hey! Can you put a different caliper on the rear? I hadn't heard of anyone doing that but if it's a possibility count me in!Can you tell me what is needed or point me to a thread on the subject?

Hi @syscrusher! Yes you can put a front right (throttle side) R6 calliper on the rear of a MKII Venture. It is plug and play with no spacers, washers etc needed......I have done this on all my Ventures and it works fine with the one small exception that the bleeder valve is no longer at the highest point on the rear when it is bolted on to the swing arm..Mother Yamaha designed it to be installed in the upright position not on it's side like it is on the rear swing arm...therefore you need to bleed the R6 calliper while it is not mounted, but just with the brake line connected (the brake line is long enough for you to bend it to the right position so the bleeder valve is pointed up, also stick a spare brake pad or piece of wood in there to fill the gap that the rotor would be in soy can pump the brake to build pressure and not have to worry about pushing the pads together or popping the pistons out) That is how I get all the air bubbles out. If you don't tilt it you will never get it bled properly and will always have a soft pedal...don't ask how I know. Once it is bled you can bolt it right in again and you are good to go. Here is a pic of a R6 Gold Dot installed on the rear of one of my 1986 Venture Royale's (see how the bleeder valve is on the low side when it is installed).

 

[ATTACH=CONFIG]105441[/ATTACH]

Edited May 24, 2016 by VanRiver

[VanRiver]

Thanks for the reply and photos. The rotor is stock Yamaha and the thought of fork damage did cross my mind. I have a 93 Venture that I can try the R6 caliper on and see if I get the same fitting issues. It seems that I have the correct R6 caliper unless someone chimes in to the contrary. Let you know how it goes.

 

Yup that looks like your regular run of the mill R6 calliper....so nothing noticeable wrong there....That 1mm you need, is that on the inside or outside of the rotor, or in other words which side is rubbing? I guess you could add a washer or you could mill 1mm off the contact surface of the mounting bolt location on the calliper depending on the side you need the room on......but to be honest I personally would rather figure out the root cause of misalignment as the last thing you want is screwed up front end geometry or potential front braking issues. Nothing like a high speed wobble in the forks/steering or not being able to stop a 800lb motorcycle to leave a nice brown stain in your shorts during a ride. But that is just my opinion of course, I'm getting more risk adverse in my old age! I'm too old to die!

[bobber]

Yup that looks like your regular run of the mill R6 calliper....so nothing noticeable wrong there....That 1mm you need, is that on the inside or outside of the rotor, or in other words which side is rubbing? I guess you could add a washer or you could mill 1mm off the contact surface of the mounting bolt location on the calliper depending on the side you need the room on......but to be honest I personally would rather figure out the root cause of misalignment as the last thing you want is screwed up front end geometry or potential front braking issues. Nothing like a high speed wobble in the forks/steering or not being able to stop a 800lb motorcycle to leave a nice brown stain in your shorts during a ride. But that is just my opinion of course, I'm getting more risk adverse in my old age! I'm too old to die!

 

Rubbing on the outside of the rotor. I have decided, as you say, to try and source out the root of the problem before I try any other remedies. I'm going to try installing the other R6 caliper on the other side and see if the same issue pops up. Anyway, many thanks for your input. I noticed that you live nearby in Dewinton, I used to be a member of that fine community. If your up for a cup of java sometime, like to see what else you've done with your Ventures.

[BlueSky]

If you are not de-linking the brakes, you shouldn't put a R6 caliper on the left side. It upsets the balance that the proportioning valve is designed for.

 

Skydoc sells rebuilt R1/R6 calipers for the front and an FJR rear caliper and ss lines that de-link for the Ventures if ya got the money.

[bobber]

Just an update: I installed both R6 calipers on the front of my 89. It is exactly the same issue with both sides...the caliper casting rubs on the outside surface of the rotor. Consistent on both sides. I then installed both calipers on my 93 and although I have some clearance ... it just clears and does not rub. I have measured all the related distances on the 89 and compared with my 93, it all checks out. There does not seem to be any damage to the forks or anything else for that matter. I need 1 mm to center the rotor in the R6 calipers for both sides. I am considering machining off the caliper at the mounting holes which will give me the required distance (1 mm).

[VanRiver]

Hey @bobber.......wow I didn't even notice you were in Calgary! I'm so used to chatting with my American friends on this site, and low and behold here is a member right in my back yard!!!

 

Absolutely, it would be great to get together for a "meet and eat"! I would love to see your scoots too! I'll PM ya and we can schedule a meeting.....if it ever stops raining here!

 

Hope you had a great Canadian May long-weekend!

 

Rubbing on the outside of the rotor. I have decided, as you say, to try and source out the root of the problem before I try any other remedies. I'm going to try installing the other R6 caliper on the other side and see if the same issue pops up. Anyway, many thanks for your input. I noticed that you live nearby in Dewinton, I used to be a member of that fine community. If your up for a cup of java sometime, like to see what else you've done with your Ventures.

[skydoc_17]

Hey Bobber,

The issue is with the spacing of the FRONT WHEEL! You can "trim" the front wheel spacers and decrease the span between the front forks. I have seen this before.

Not to get off topic, but the problem with putting a front R1 Caliper on the rear of a Venture is the fact that the bleeder is not located at the top of the Caliper Body.

Bleeding this caliper is a real pain unless you remove it from the rotor, bleed it, then return it to the rotor.

I offer a progressive engagement,(2 big pistons, 2 little pistons) 4 piston caliper with the bleeder in the right location completely rebuilt. If anyone is interested, please feel free to PM me.

Earl

[Condor]

If you are not de-linking the brakes, you shouldn't put a R6 caliper on the left side. It upsets the balance that the proportioning valve is designed for.

 

Skydoc sells rebuilt R1/R6 calipers for the front and an FJR rear caliper and ss lines that de-link for the Ventures if ya got the money.

 

With all due respect, that just ain't true. I put a set of R1 calipers on my '83 with '86 forks, and kept the stock rear caliper since the stopping power of the rear was minimal anyway. I kept the brakes linked. They worked fine. The left/rear was much improved.

[BlueSky]

If the front left braking is improved, it would have to change the balance of the braking when you depress the pedal to some degree. Skydoc told me the same thing.

[Condor]

Ok, what's the stock ratio, and then what does that ratio change to when using an R1??

[BlueSky]

The balance afterwards could be better. All depends on how good Yamaha was at selecting and designing the proportioning valve. But IF the R1 caliper does a better job of braking, it would have to change a tad. With the 4 piston Gen I front calipers, does it really do a better job?

[Condor]

How much better?? The stock ratio is 70/30, and that's why I'm asking. What is the difference in the ratio that the R1 would cause?? Personally I didn't experience any great change other than the braking was improved. A bunch of members have already done the R1 swap and so far I'm not aware of one that voiced that they experienced any problems with the linked brakes and the R1. Maybe it has changed, but is it great enough to cause problems with the system, and tell folks they should not put an R1 on the left side?? Without backing it up with actual data it's not enough to just make that statement.

 

Here's my spin on this thing. The proportion valve distributes the applied pressure into 70/30 no matter what caliper is on the front end. If a caliper does a better job in braking then it's an improvement. Since the front brakes have both been improved, and the front brakes supply the majority of the braking on a bike the actual braking pressure on the front and the rear will actually decrease due to caliper efficiency. One benefit would be that the chance of high siding will decrease, and overall braking will increase with less effort. My 2¢

[bobber]

Hey Bobber,

The issue is with the spacing of the FRONT WHEEL! You can "trim" the front wheel spacers and decrease the span between the front forks. I have seen this before.

Not to get off topic, but the problem with putting a front R1 Caliper on the rear of a Venture is the fact that the bleeder is not located at the top of the Caliper Body.

Bleeding this caliper is a real pain unless you remove it from the rotor, bleed it, then return it to the rotor.

I offer a progressive engagement,(2 big pistons, 2 little pistons) 4 piston caliper with the bleeder in the right location completely rebuilt. If anyone is interested, please feel free to PM me.

Earl

R6 BRAKE UPDATE

 

Thanks for the input Earl. I examined the front wheel (axle) to see if had the correct spacers but it did not cross my mind to trim the current ones. As it is, I ended up machining the calipers 1/32" which amounted to little more than removing the anodizing from around the mounting holes. The machining was a little pricey but the calipers now line up perfectly. I just got back from a 10 day trip through Northern British Columbia and I am very impressed with the upgrade. I now have much better stopping power which was exactly what I wanted when I started this project. It wasn't exactly "plug and play" but pretty close. (Hope my recovery from knee surgery goes half as well)

Many thanks to all those who replied! I can't tell you how much I appreciate the good folks on this website.