Master cyl options?

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Strange that it would be something they’d change. I don’t know what year mine is buts it’s 14mm. Guess I’ll have to search for an earlier one.
Thanks for the replies.
 
The masters changed as the later ones do not have the screw in hole for mirrors, the mirrors being relocated to the fairing. No idea about the bore change.
 
There are at least 3 different bore sizes for the FJR masters. I think the 2005 is the ideal year with right bore and the threaded mirror mounts
 
Here is a 16 mm Magura front brake master cylinder. No threaded hole for a mirror. $133

Magura® 0222020 - 225™ Right Hydraulic Brake Master Cylinder Kit - MOTORCYCLEiD.com

'Advanced search' is your friend. Do some homework. From an earlier thread ([email protected]):

This is the info I found when I was researching last year:

Here is some updated info on FJR masters

FYI

16mm=0.629"
5/8"=0.625" (Ed. note: the OEM VMX12 size)
14mm=0.551"

Another FYI on FJR bore diameters:

03' thru 05' all have the same bore diameter in the clutch master. 14mm
03' is the ONLY year the FJR had a front brake master with 14mm bore
04'-05' FJR front brake masters are 15mm
04'-05' FJR front brake masters for ABS equipped bikes are 16mm.

I have a couple FJR brake masters off of the '05 with ABS. It is a 16mm bore which is basically the same as our 5/8" master so it won't offer a different feel in braking action BUT it does have a 5 position adjustable lever and the OE connectors for the brake switch plug right in. Actually, I have more than one if anyone is interested. Looking to get $70.00 shipped out of one.

They are currently NOT drilled and tapped for the stock vmax mirrors but the boss is there. I was planning to do so but tap it with regular threads vs. reverse threads. That way you could use any mirror you want without those ugly adaptors. If you wanted to use stock mirrors I could throw in a stem from a left mirror and then you'd be golden.

(106) FJR Master Brake and Clutch cylinder questions | Page 4 | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)
A last reminder (ibid.) to use the advanced search-take the initiative.
 
Last edited:
Any feedback on the brake master? I’m considering these.
Use the advanced search-'search' rt-hand corner, 'advanced search.' The amount of feedback is proportional to the effort you expend to access it. Initiative rewards the inquisitive.

I'm no mechanical engineer, but I assume master cylinders of same-size bore are going to perform much the same.
 
Last edited:
Use the advanced search-'search' rt-hand corner, 'advanced search.' The amount of feedback is proportional to the effort you expend to access it. Initiative rewards the inquisitive.

I'm no mechanical engineer, but I assume master cylinders of same-size bore are going to perform much the same.
Yes. Most are aware of the search feature. Not sure if you intend to sound condescending or if it’s just your approach. I replied to patate657 for his first hand experience with the product.
Thanks
 
Sorry Having carb problems with my bike right now (On top of having 2 bikes I'm parting out right now) and haven't had time to install the aftermarket front brake master cylinder yet. When I can get my old a$$ in forward gear, I also need to install the clutch and brake master cylinders I bought for my v65 also....
 
(19) What did you do to your Vmax today? Part 2 | Page 608 | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)

(19) Leaky clutch master cylinder | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)

(19) Aftermarker front brake and clutch replacements | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)
A good thread w/lots of options

(19) brake and clutch master replacement question | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)

(19) Ebay Master cylinder set??? | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)

(19) Remote Master Cylinder Reservoirs | Yamaha Star V-Max VMAX Motorcycle Discussion Forum (vmaxforum.net)

A few minutes using the search function shows many aftermarket options available for the consumer. Options are out-there if you look. Price, style, remote reservoirs, piston size, changing master cylinder piston size because of number of caliper pistons and volume, and more. This topic is a popular one. Time spent on a few minutes' research could show the inquisitive many options. A minimal investment of time shows the variety of choices available.
 
I'm no mechanical engineer, but I assume master cylinders of same-size bore are going to perform much the same.

If we liken the displacement of a master cylinder to that of a cylinder and an engine, and we quickly realize that displacement is a function of both bore and stroke. So, the length of the stroke is going to also have an affect. Not sure I’ve ever heard that metric applied to master cylinders, but it is a factor.
 
If we liken the displacement of a master cylinder to that of a cylinder and an engine, and we quickly realize that displacement is a function of both bore and stroke. So, the length of the stroke is going to also have an affect. Not sure I’ve ever heard that metric applied to master cylinders, but it is a factor.
Given the space involved, the stroke difference I suspect is minimal, though I haven't measured it. The bore difference seems to be a much more reliable indicator of changes in the hydraulic function. If you look at a chart on the differences in the ratio, mentioned are # of pistons and bore size, where length of stroke isn't even tabulated. That tells me the length of stroke isn't enough of a determinant to even enter the equation. Properly-bled, there isn't enough of a range of motion before locking-up the caliper piston(s) to the rotor(s), for length of stroke to play any significant part. Again, I'm no mechanical engineer, so this is purely anecdotal, and references master cylinder ratio charts designed and tabulated by those whom I assume, are M.E.'s.

Examples:
Brake Master cylinder to wheel cylinder ratios (ducatimeccanica.com)

Front Master Cylinder Ratio Chart (vintagebrake.com) This is the chart I've used for my projects. I also communicated with its creator ('V'ger') and he answered questions I had about the chart.

 
Last edited:
Sorry Having carb problems with my bike right now (On top of having 2 bikes I'm parting out right now) and haven't had time to install the aftermarket front brake master cylinder yet. When I can get my old a$$ in forward gear, I also need to install the clutch and brake master cylinders I bought for my v65 also....
When you swapped the clutch master did your engagement point for the clutch change from stock? I swapped with the eBay 5/8 bore master and it went from the end of the lever throw to right off my grip. Just wondered if you experienced similar?
 
When you swapped the clutch master did your engagement point for the clutch change from stock? I swapped with the eBay 5/8 bore master and it went from the end of the lever throw to right off my grip. Just wondered if you experienced similar?
If you were at "end of lever" release you had issues. You probably had a combination of air in the lines, old fluid and worn contact points between the level and plunger.

Release should be closer to the grip, not all the way at the end of the lever throw. I'm still running a stock 2007 Vmax and my release is not very far off the grip.
 
If you were at "end of lever" release you had issues. You probably had a combination of air in the lines, old fluid and worn contact points between the level and plunger.

Release should be closer to the grip, not all the way at the end of the lever throw. I'm still running a stock 2007 Vmax and my release is not very far off the grip.
Thank you! This is my first vmax. Hard to tell what is considered “normal”. Hopefully get it out on the road this evening and try it out. Ohio weather has not been the greatest.
 
If you were at "end of lever" release you had issues. You probably had a combination of air in the lines, old fluid and worn contact points between the level and plunger.

Release should be closer to the grip, not all the way at the end of the lever throw. I'm still running a stock 2007 Vmax and my release is not very far off the grip.
Parminio- could I have a bad/blocked bleed screw on my clutch? I’m able to bleed it the traditional way, but it will not accept a reverse bleed. I was able to do the reverse method for the front and the rear brakes so I understand the procedure. Unless I’m doing something stupid. I’m using a syringe with tube over the bleeder. Cracking it open and trying to inject the fluid. My clutch is trying to engage 1/8” off my grip and shifting is noticeably harder. I’ve let the engine heat up to operating temp prior to testing.
 
20 Pc. Carbide Rotary Micro Bit Assorted Set (harborfreight.com)

Clean the hole closest to the banjo bolt and flush the system again, you probably have crud floating to and away-from that orifice, causing you intermittent blockage.

You may need to remove the banjo bolt, and put the end of the hose connecting to the master cylinder into a reservoir, and then reverse-flush. To thoroughly clean the system, remove the master cyl ass'y. and flush it on the bench, to ensure removal of whatever is preventing your reverse-flush from happening.

Depending upon the age of your bike, you may have a deteriorating hydraulic rubber tube, sloughing-off pieces of the inner passageway, what a medical professional would refer to as the 'lumen (the inner passageway).' A heart attack or a stroke can be caused by the same principle, a broken-off piece of plaque or an agglutination (sticking-together) of blood cells migrates to a point of constriction in their path, and suddenly, you have a partial or a total obstruction, in the cardiac muscle, you have a myocardial infarction, a heart attack in layman's terms. In the brain, it's a stroke. In the lungs, it's a pulmonary embolism. In your bike, it's a malfunctioning clutch circuit or a malfunctioning brake circuit. Replacement of that brake line or the clutch line is indicated, if the rubber is deteriorated to the point where it keeps depositing debris into the system, and interfering with proper hydraulic circuit operation.

If the issue keeps happening after you believe you've thoroughly flushed your bike's hydraulics, then I would have a high index of suspicion that you have a deteriorated hose inner-diameter. If the brake fluid quickly becomes dirty after you have flushed the system, upon re-filling it, or the issue soon re-appears, I'd say that is sufficient of an indicator to call for hose replacement. Sean Morley [email protected] has new ones, or your dealer. CaptainKyle [email protected] can also help you.
 
Last edited:
Parminio- could I have a bad/blocked bleed screw on my clutch? I’m able to bleed it the traditional way, but it will not accept a reverse bleed. I was able to do the reverse method for the front and the rear brakes so I understand the procedure. Unless I’m doing something stupid. I’m using a syringe with tube over the bleeder. Cracking it open and trying to inject the fluid. My clutch is trying to engage 1/8” off my grip and shifting is noticeably harder. I’ve let the engine heat up to operating temp prior to testing.
What @Fire-medic said.
 
Update… I was able to reverse bleed the master cylinder and get the bike back on the road. She is shifting smoothly and running well. I took the advise and back flushed the cable without the master attached. I also cleaned out the master. Thanks for all the help!!
 
That's what we all enjoy hearing in a report of work performed. Congratulations. No matter what you're experiencing, chances are someone on here already dealt with the same issue.
 

Latest posts

Back
Top