Kawasaki voyager and motor trike brakes don't mix!!

[Chappy KC]

I recently purchased a Kawasaki Voyager 1700 that had been triked out with the Motor Trike Challenger kit by the dealer. Since day 1 the rear brakes have needed to be pumped to get anything resembling "brakes" in the rear. I notified MT and they said to give it 1000 mile to let things break in and take it back to dealer for the 1000 mile check and have them bleed them. I took it in at 1600 miles and everything was checked out and the brakes were bled but they are no better. The dealer is waiting on a call back from MT on how to solve this problem. He says it may need a larger master cylinder. It seems I have read about that on others posts. Can somebody here tell me how big the Kawasaki Master Cylinder bore is and maybe what size I may need to go to? And then even where this might be purchased?

[stinger608]

The master cylinder bore size wouldn't really have anything to do with your need to "pump" the brakes up. That sounds like air in the system somewhere to me. I suppose though, it might now that I am thinking about it. If the master cylinder bore is too small and wasn't pushing enough fluid on first push. Hmm, maybe you might have to go to a larger bore.

It could also be a faulty master cylinder as well. Even though it is new that doesn't take a bad unit out of the equation.

[icedad]

I can't tell you for sure, but in a semi truck and trailer, there is an equalization valve that make both the front and rear act equally together. Cars have the same thing. I don't know if this holds true for a trike, but it only makes sense.

[Chappy KC]

Icedad...I think on trikes and bikes it would be considered having linked brakes. I am not sure if they work exactly like you are talking about. Anyway, mine are not linked. I just think that the untrained young fellow did not follow the specific step by step process for bleeding these brakes. And I am reasonably sure he used a power bleeder. When I get some free time wifey and I will bleed them manually and do it several times just to make sure we have done all we can do. Then I will post again the results. Hopefully it will be a retraction!

[FuzzyWuzHe]

The master cylinder bore size wouldn't really have anything to do with your need to "pump" the brakes up. That sounds like air in the system somewhere to me. I suppose though, it might now that I am thinking about it. If the master cylinder bore is too small and wasn't pushing enough fluid on first push. Hmm, maybe you might have to go to a larger bore.

It could also be a faulty master cylinder as well. Even though it is new that doesn't take a bad unit out of the equation.

Plus 1

[Rmitchell55]

Chappy KC

Did your bike have ABS brakes? When I converted my 09 Voyager with ABS brakes, it took me several days to get the brakes half way decent with enough stopping power. Initially I used the rear hose that was on the bike with ABS and just coiled up the excess. Bad idea trying to get all the extra hose to slope upward. Champion calipers have two bleed ports, one at the top and bottom so they are reversible. I ended up pulling the calipers and turning them upside down and bleeding both ports. I finally removed all the ABS hoses/tubing and running hoses from the master cylinders to the brake calipers.

[Chappy KC]

Chappy KC

Did your bike have ABS brakes? When I converted my 09 Voyager with ABS brakes, it took me several days to get the brakes half way decent with enough stopping power. Initially I used the rear hose that was on the bike with ABS and just coiled up the excess. Bad idea trying to get all the extra hose to slope upward. Champion calipers have two bleed ports, one at the top and bottom so they are reversible. I ended up pulling the calipers and turning them upside down and bleeding both ports. I finally removed all the ABS hoses/tubing and running hoses from the master cylinders to the brake calipers.

I have thought about doing brakes like on a tractor. 1 master cylinder to 1 brake and 1 master cylinder to another brake and 2 foot pedals that would be linke with a bracket. That would make for plenty of fluid to actuate the brakes and also provide for very tight turning radius.

[Loner]

Not all brake master cylinders on motorcycles have enough volume to pump two slave cylinders as found on their new trike conversion. Your discussions above don't consider the other variable of the master cylinder - stroke. On a motor cylinder volume is a product of bore x stroke. Same with a master cylinder. Yes, your stock cylinder probably has an adequate bore size (smaller is better to get more leverage). But it is the stroke of the piston in that bore that needs to be longer to get more fluid pumped out with each pedal push. That's why the mechanic said it needed a bigger master cylinder (more stroke and volume), so it could pump more fluid each push. That's when you can either shop salvage shops or order aftermarket replacement. Companies such as Jamar make master cylinders with different specifications and mounting to apply to most needs. There are other suppliers as well. Also keep in mind that using disk brakes versus conventional will require different master cylinder specifications, as disk calipers do not require the same volume as the standard servos (as found in many trike conversion kits).

There is a bandaid in a situation like yours if you brakes work satisfactorly once pumped up. You can add a 2 pound pressure valve that goes in the brake line near the master cylinder. That will allow rake pressure to work normally when brakes are activated, but will maintain 2 pounds of pressure in the system so the systesm stays full of fluid and does not drain back to the master cylinder when not being used. Pedal pressure should then be ready when activated with little to no hesitation. These 'residual valves' are available from most dune buggy or custom vw outlets (plenty online).

Finally, it is a rare case that multiple brakes have been linded where they are balanced all the way through a braking cycle. Theoretically it looks good on paper, but in reality it just will likely not work. For example someone mentioned linking a trikes rear brakes and front break into one actuator (or even two actuators pushed by one pedal). You have linked two huge contact patches (tires touching the floor) with one quite small patch up front. You are not going to get the same even braking pressure no matter how you set the equalizer valve(s). Been there, done that. Gave up.

Have fun and I hope it gets solved soon.

[Chappy KC]

Thanks Loner! That is good info. But if my disk brakes take less to operate than the drum brakes, I should be able to get some stopping power from my current setup. How did you modify your HD trike conversion? Maybe I should get the HD master cylinder? Looking for that longer stroke is sounding like the fix.

[Chappy KC]

Trike returned to me on 18 June with good brakes. Seems the calipers were not aligned correctly with the rotors and only a piece of the pad was making any kind of contact. I blame that on MT manufacturing. Then I blame the original tech that built it for not fixing them. Then again I blame MT training process for letting it leave its facility like that.