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1998 brake system service

15 posts Started 7 Oct 2018 Last recovered post 15 Oct 2018 Wayback Machine snapshot 18 Jul 2019

#1

Hello all, I was wondering if there is a step by step guide on disassembling and cleaning calipers on gen 5 vfr800fi? 

#2

Got the factory service manual? You can download from this site.

#3
22 minutes ago, mello dude

Got the factory service manual? You can download from this site.

Thanks, i found that and will read it over the next while. Think i should try and clean system before replacing anything. I was looking at HEL brake lines, wavy discs and short levers. One step at a time.

#4

short levers=less force applied

#5

Not sure whats going on with this... I have just focused on bleeding the front right centre nipple with a vacuum pump and just get a little fluid and loads of bubbles  Doing this over the last few days for about 5 mins each time but its the same every day. Checked the rear master and looks like no brake fluid has gone down. Also used manual way with 10 brake pumps, open nipple press brake and close before slowly releasing rear brake pedal  I have phoned my mechanic and he will collect bike this friday to service the brakes as i do not want to start pulling the bike apart. 🤔 When its running properly, i will start upgrading it. Just want to get it 100% and enjoy it as i only bought it a few weeks ago.

#6

Using a vacuum pump on a stock nipple will pull air through the threads. 

They need to be sealed with thread tape or the like for it to work. 

#7

If the traditional bleed method of, pump, hold, open, close, release is too tedious, try speed bleeder nipples or an in-line bleeder with a one-way check valve, makes for much easier bleeding. I believe Motion-Pro has two types of in-line bleeder tools. If I recall correctly, one tool has a hose on either end of the check valve and the other one has a socket built into to the tool, so you can open the nipple and leave the tool attached.

Then again if your mechanic is willing to do it and isn’t going to charge you too much, that would be another route too.

#8

Thanks for the reply. I will start fresh on friday with manual pump. Might tell mechanic to hold off. Its just getting the time to do it. I might invest in speed bleeders? Is this right ? EBay seller quote:

Simply 1/4 turn open and then click on the hand or foot brake lever. Due to the vacuum pressure the ball valve and excess opens

Air can escape. As a rule, is the braking systems completely deflated after only five times the pump and the bleeder valve can be completely closed again

#9

The description sounds right but does seem to be over simplifying how many times it takes to clear the air out of a line. There are a few makers of these bleed nipples, Russell, Goodridge and Speed Bleeder to name a few. Regardless of which one you choose, essentially, yes, you open the bleeder, press the pedal or pull the lever and it allows fluid to flow out, no need to close the bleeder before releasing pedal/lever. You do need to be cautious and keep your eye on the reservoir, make sure it doesn’t go too low as to introduce air into the line from the start of the line. 

#10
17 hours ago, Charlie Not sure whats going on with this... I have just focused on bleeding the front right centre nipple with a vacuum pump and just get a little fluid and loads of bubbles  Doing this over the last few days for about 5 mins each time but its the same every day. Checked the rear master and looks like no brake fluid has gone down. Also used manual way...

Not sure there's a connection between these parts on the 5th gen... Only the front left,  and even then, although memory may fail me, levels at the rear reservoir may not be affected. I would have to consult the service manual, it's been 10 years since my 5th gen days.

#11

My bad.

I knew there was an increased bias in the distribution of hydraulic pressure to the front brakes in the CBS system from the 5th to the 6th gen.

Nonetheless it went from one piston on the right to none, on pressing the rear brake pedal, respectively.

I had thought the changes might have all taken place in the LHS calliper.

5th

[image: 291738685721c209099978d01b75779c.jpg&key=754024208bdc2bfd2570d6e955890633331c83b2b90e08bac6f0f880b539084c]

6th

[image: 12e4d88e61d759993e7c270f86826a5d.jpg]

#12

I don't think you're reading that drawing correctly. 

The 6G still uses the centre rear piston. 

You just can't bleed it via front lever, (you can't on the 5G either), you need to squeeze the secondary master to do it. 

I just think the last drawing was changed to reflect where you can bleed by pressing front lever. 

#13
VFROZ I don't think you're reading that drawing correctly. 
The 6G still uses the centre rear piston. 
You just can't bleed it via front lever, (you can't on the 5G either), you need to squeeze the secondary master to do it. 
I just think the last drawing was changed to reflect where you can bleed by pressing front lever. 
Yep, exactly, the centre rear piston is still actuated by the front brake system, via the secondary master which forms a part of the front left caliper mount. That hasn't changed.

Anyway so my suspicion that the OP shouldn't, as he seemed to expect, see a drop in the rear reservoir when bleeding the front right calliper holds true.
#14
22 minutes ago, Auspanglish

Yep, exactly, the centre rear piston is still actuated by the front brake system, via the secondary master which forms a part of the front left caliper mount. That hasn't changed.

Anyway so my suspicion that the OP shouldn't, as he seemed to expect, see a drop in the rear reservoir when bleeding the front right calliper holds true.

You are correct sir. 

#15

Thanks for all the feed back👨‍💻. I ended up calling my mechanic as i only bought the bike off him a few weeks back. He apologized🙏for the hassle and i will call over to collect the bike tomorrow. 🏍💨 

End of thread · 15 posts recovered Wayback Machine snapshot 18 Jul 2019