Front brake mastercylinder upgrade.

[jimmyenglish]

Hi everyone, just completed a 4k ride with the R1 upgrade, Vmax rotors, stainless lines and EBC HH pads. Wow, what a diff. However, I can really notice the limitations of the stock, front master cylinder when leaning on them. What's the upgrade for the master cylinder?

 

Also, has anybody come up with a fork spring solution other than the progs? I just put them on before the trip (block off plates, AD's removed) and once most of the oil blew passed the seals, they mellowed a little. Still, I'm not liking them at all. Way too stiff. I look down at the forks and unless I really lean on them or hit a huge bump, they don't compress at all! I put progs on my 92' BMW K75 back in 2006 and had the exact same experience. I have no spacers installed for preload at all.

 

I would think a two stage spring would be awesome. Perhaps cutting the progs down and adding something softer in the bottom? Has anybody come up with a better solution? Perhaps I don't have them dialed in correctly but even with no oil at all they're too stiff. I was using 10wt. Also, I'm sure it's not the weight of the bike. I had the bike and trailer fully laden weighed on our last night: Bike = 933lbs, trailer = 435lb. Tounge weight is around 20lbs. I'm 190 and my wife is 145. Still seemed incredibly rigid.

 

Thanks everyone! Great forum!

Edited August 30, 2012 by jimmyenglish
forgot to add stuff

[GaryZ]

Hi everyone, just completed a 4k ride with the R1 upgrade, Vmax rotors, stainless lines and EBC HH pads. Wow, what a diff. However, I can really notice the limitations of the stock, front master cylinder when leaning on them. What's the upgrade for the master cylinder?

 

Also, has anybody come up with a fork spring solution other than the progs? I just put them on before the trip (block off plates, AD's removed) and once most of the oil blew passed the seals, they mellowed a little. Still, I'm not liking them at all. Way too stiff. I look down at the forks and unless I really lean on them or hit a huge bump, they don't compress at all! I put progs on my 92' BMW K75 back in 2006 and had the exact same experience. I have no spacers installed for preload at all.

 

I would think a two stage spring would be awesome. Perhaps cutting the progs down and adding something softer in the bottom? Has anybody come up with a better solution? Perhaps I don't have them dialed in correctly but even with no oil at all they're too stiff. I was using 10wt. Also, I'm sure it's not the weight of the bike. I had the bike and trailer fully laden weighed on our last night: Bike = 933lbs, trailer = 435lb. Tounge weight is around 20lbs. I'm 190 and my wife is 145. Still seemed incredibly rigid.

 

Thanks everyone! Great forum!

 

I also would like to know of a front brake master upgrade . . . So far as your Progressives, my only thought is that something is not assembled correctly. I have Progressives on three bikes and all have done exactly as advertised. There is better - softer small bump action that progressively gets stiffer. My VR has been put on a diet by removing a number of chrome farkles. The total weight of me and the VR is probably about the same as you and yours. I am running 7awg fork oil and the anti-dives are disconnected. The spacer that came with the springs was substituted for the stock metal sleeve and the forks work very well. Could the fork assembly be binding?

[bongobobny]

For the 2nd gen's it is a 14mm bore master, and it would probably work with 1st gens as well...

[friesman]

When Rocket put my progressives in, we talked about ride and he suggested if I wanted a softer ride we should try not putting their spacer in, or finding something shorter so it doesnt have as much preload. Mine have been running great for about 4 years now since the owrk was done not using any spacer. (But ive noticed this year the ride is getting a bit soft, so I may have to find something to space it a bit).

 

Brian

[Geobob]

For the 2nd gen's it is a 14mm bore master, and it would probably work with 1st gens as well...

Hay Guys, I just tried to rebuild my front break master cylinder on my 1988. The K&L kit that was advertised to fit (232-4146) is for a 16 mm bore and my 1988 has a 14 mm bore. Does anyone know what the correct K&L kit number is. They are readily available so it would be convent to just order the correct kit but they do not list the size.

 

Maybe I will just order the kit for the new Venture.

 

Ok after a bit more research for anyone interested. I got on a site that sells OEM parts and got a part number for the rebuild kit. 4H7-W0041-50-00. On another site they had a photo of the kit that is listed as the correct size for the 1988. It has a ruler laid out below it and it shows the rubber ring that is approximately the size of the cylinder bore. It was just about 1/2 inch so it is likely for the 14mm bore cylinder. I took that OEM part # and put into the search bar for Amazon and low and behold up came the part but it is listed for a several ATVS over several years. It does list the part number so it is safe to say it should work. $22.95 with free shipping. Now lets discuss what other master cylinder will work on these handle bars that is 16mm since I think that might be better for a delinked system that I put together. I can also suggest not staking 2 lines on the master cylinder. Better to run just one line and split it down below. The two lines took up too much room up top.

Edited March 21, 2020 by Geobob