06 Beta Rev 80 front brakes

[Rob W]

Has anyone had trouble with spongy front brakes on their beta 80's. We have a brand new 06 model that neither Dave Ryan (Beta Racing) nor myself has been able to get working satisfactorily. There were obviously problems with both the master cylinder and the caliper unit that came with the bike. The master cylinder was not drilled correctly so that fluid did not enter the cylinder cleanly and, more particularly, air could not leave the system. A new master cylinder (from a rev3) then revealed that the caliper unit was flexing and letting air back in along the machined faces (the halves did not align properly). I sent the whole lot back to Beta Racing and Dave had a go at it. Dave got new bits and then tested it on his cycle for a while and apparently had it going fine. I have just recieved it back this afternoon (complete, bled and operating) and put it on. James tried it out. The front brake was spongy and got worse with 30 seconds of use. The point of braking is vague and the lever is not crisp.

I am at my wits end as this has been going on since the beginning of January. I cannot see any flexing in the caliper unit. Could the Rev 3 master cylinder mated to the twin spot caliper be the problem? I wouldn't think so. Could air mail transport have introduced or caused an air bubble? Most likely. Oh well - back to bleeding for the ten millionth time!

We also have a rev 50 with a completely stock set up. There is no problem with it. It is crisp, sharp and effective.

Whilst waiting for this to be sorted Kal Daley (KD Mototrials) has lent us a four spot system from a Rev 3. It is brilliant on the 80. Does anyone have a spare 4-spot they can sell us?

[BJ]

Rob

Of the many bikes you have there can you do some swapping of bits????

Can you try a master cylinder off something else to see if the caliper is working ok?

Maybe scuff up the pads with some sand paper?

Ease off with the WD-40 and tell the kid to use less Kitten Car Polish on the shiney bits????

Or are you like Beechey who expects dynamite brakes and lock ups after 3mm of travel? He rode my 175 on the weekend and said the front stoppers didn't work Then he felt my SY and found out I like the lever to hit my knuckles before it starts to do anything! It must be a left over from my high speed days....no wonder I can't do nose wheelies

You already know this I'm sure, but some pads take a long time to bed in, maybe these little fella's are just worse than most???? The TY-S 175 was very soft on the front for quite a while but now it has real bite (if you pull the lever into your knuckles). I know I haven't helped but at least i tried!

[jmclean]

Hi Rob,

From what you tell us about what you've done, I doubt there's still air in the system. If there was, you'd find that the lever could be pulled in hard, and while being held with the same amount of pressure, the lever would continue to 'give' some more until maybe the the lever came right into the handlebar.

I've read a few articles on the TrialsCentral forum about getting disc brakes really hot and dousing them with water to get that firm "run-in" feeling.
There is no doubt that disc brakes are initially spongy after re-assembly. The forum posters swear this really does work.

Also when reassembling the front wheel, try spinning the front wheel fast and hard applying the front brake, and hold it on hard, while a second person does the final tightening of the front axle and caliper mounting bolts. This will assist in getting a perfect disc to caliper alignment.

Good luck, Jim

[KTMSprocket]

We have a Beta Rev50 and the brakes are good like you said.

The problem still sits with the dealer - dont put your hand in your pocket twice for the same thing.