best way to seperate brake calipers?

[fallenmikethebike]

Certainly looks OK, BUT, some details might have been nice, it could be made out of yoghurt for all we know.
Mike

[fishtail]

well after leaving out a day or 2 in the rain ( covered) had a bit of surface rust on disc

after the ride came back and can total see that the disc is scored to bejesus - got rust circles! where rust wasnt removed by the riding..

any one have a disc brand I can shop for? preferably not yogurt.. I want forged by men drinking iron bru

[fishtail]

well after yesterdays ride out

brakes are better - but seem to need a pump on the lever to firm up occasionally - ( leaky seals? )


and they are squealing like an old bus!

http://www.youtube.com/watch?v=b2AxzMUz ... re=g-all-u[/youtube]

[fishtail]

http://www.youtube.com/watch?v=b2AxzMUz ... re=g-all-u

[karlloss]

you says you've already fitted a braided hose and new caliper seals, if the caliper seals are leaking you'll see the weeping fluid around the pistons, likewise if you peel back the rubber dust boot on the master cylinder at the lever and it's full of fluid then then seals are leaking. However if you need to pump the lever to firm up it could be that there is still air in the system which will require bleeding, or if it could be that the master cylinder seals are worn and fluid is leaking past the seals but not externally, the way to test is if you grab the lever sharpley and pull back fast (as if doing and emergency stop) and the lever is firm, and then release and pull back slowly and steady as doing so the lever comes back to the bars this indicates the master cylinder seals are worn. The way the test works is that the parid and sharp pull suddenly pushes the seal against the fuild which slightly expands the seals, thus they work as they should forming a seal in the bore, yet if you pull slowly and stedy the seal doesn't have the sudden 'shock' and therefore doesn't expand as much and the fluid weeps past the seals, we're only talking micros here but enough to cause the fluid to seep past. The cure is to fit new seals and maybe hone out the cylinder, or alternatively just replace the master cyclinder, most master cylinders will fit just ensure the bore size is the same or larger, which is marked on the cylinder in eithe inches oir millimeters.

[fishtail]

thanks Karloss - will investigate further..

I did buy seals - but hadnt the guts to get in there yet - but will probably give it a go this week..

last time my local shop didnt have master cyclinder seal kit in stock - will check back..

as a heads up this bike hasnt had a lot of love in the past - so might as well do all the seals in one go..... ( ie caliper and master - )

just had the rear tire changed and the bearings were shot - they also said the the inner tube was using gaffa tape in stead of somethign to hold the valve? ( my chinese isnt as good as it could be so that might not be as accurate a translation as one might get... - they did let me off 50 p tho just cos I could speak chinese at all!

[karlloss]

The seals are easy to fit, just remember to note which way round the old ones came out. If you haven't done it before probably best to use a repair manual, don't worry if you haven't got a CRM one, any repair for a motorcycle master cylinder will show you the basic principals, just remember not to rush and note the orientation and position of every component as you strip it. Try youtube for a guide?

[njhardy]

Hurrah!!- fishy gets airborne at last in the video... see, it's not that difficult is it?? I bet you got dizzy going round and round that little track!!

[fishtail]

ha! I was airbourne on that little track too! you just cant see it~ but you're right - could only do 3 laps before dizziness...

cant believe it - didnt actually fall off the whole day.... drop strategically here and there - but thats not falling off is it ??

and to be honest when my mate was pointing the camera I thought , " ay up ! better hold back cos dont wanna be on the dirtbike crash compilation..."


whats this I hear about you selling yours then?


got the flu today - off work - watching MX how to's.....


- a lot are saying use 2nd gear for hill climbs? I've been doing ok in the dry in first ( most of em dont have much of a run up... )



any opinions on this

bugger all to do with brakes I know - havent done them yet...

[fishtail]

thanks to your test Karloss I think its the master cyclinder seals..

Decided to take no chances - will do both sets - have the caliper parts but not the master cyclinder bits.. my usual shop has no stock - so.....


I had to speak to my local honda dealer.....

- friggin annoying when they are deaf and ask you identify the bike, the part, the year................... the first guy finally gets the details correct

- he then passes me on to another guy who is also deaf and wants the same info....


grrrr - why did the first muppet ask me to repeat all the details 3 times???


then he wants my chassis number? - its taken 5 goes to get the CRM 250 part and '96 across.. a 20 digit number doesnt sound thrilling! ( which I didnt have to hand anyways! i was taking a break from a shitty job I was workign on )

which part of 1996 CRM 250 mark 3 dont you understand?>????

actually he didnt know what a mark 3 was !!! had to explain 89 was mark 1 - mark 2 was 92 and mark 3...

anyways I told him he didnt need that cos they all the same on the mastercylinder

was I right tho??

are all 3 models using the same master cyclinder?

got the feeling he would say anything to get off the phone.....


read in the manual I will need one of these to do the job? ( snap ring pliers? )

http://www.bing.com/images/search?q=sna ... ORM=IDFRIR

[karlloss]

Fishtail, you will need the pliers, also called circlip pliers. As for all CRM250 models having the same master cylinder I have no idea. You could always fit a master cylinder from any later model enduro bike, just ensure it has the same size or larger bore, this is marked on master cylinder as 3/8, 1/2, 5/8 etc. or in milimetres 18, 22 etc.
Fitting a master cylinder of a later and more available bike will make it easier to replace the seals if you need to at a later date, although probably won't need to.

[fallenmikethebike]

ha! I was airbourne on that little track too! you just cant see it~ but you're right - could only do 3 laps before dizziness...

cant believe it - didnt actually fall off the whole day.... drop strategically here and there - but thats not falling off is it ??

and to be honest when my mate was pointing the camera I thought , " ay up ! better hold back cos dont wanna be on the dirtbike crash compilation..."


whats this I hear about you selling yours then?


got the flu today - off work - watching MX how to's.....


- a lot are saying use 2nd gear for hill climbs? I've been doing ok in the dry in first ( most of em dont have much of a run up... )



any opinions on this

bugger all to do with brakes I know - havent done them yet...

The steepness and technicality of the climb will dictate the gear required, and in most cases, if it works for you, it's probably right, though the lower the gear the more chance of an uncontrolled front wheel lift there will be.
Mike

[fishtail]

hmm - but then mine starts to sound weird if I try to "pull" in too low a gear..

will have to record the sound as hard to describe.. but it sounds ( altho doesnt feel like ) the whole bike is about to shake to bits??? weird clicks and almost pings??

an uncomfortable sound..

I reckon I will try brakes next week now - seems to be raining a lot here and I am supposed to go on a ride on sunday... and the brakes are sort of working...... ( as opposed to being in pieces if I start now and dont finish by sunday )

parts for the master cyclinder gonna be about 20 quid.....

a new master cyclinder gawdknows how much???

[fallenmikethebike]

Check the drive chain alignment is true, and all in good condition.
Mike

[fishtail]

thanks! actually the chain actually does look a little bit gnarly... ( so once I fix up the brakes and put on the DEP downpipes - maybe I will get a new one.. )

to be honest I climbed some pretty steep stuff today.. seems I do prefer 1st - and being able to lift the front came in handy a few times ...


( googling how to tell if your dirtbike chain is fecked right now )