1995 CB250 caliper, any other bikes with the same one?

mrtEE · World Chat Champion Joined: 12 Sep 2005 Karma :

The front caliper on my 1994 CB250 is in poor condition and Im looking for a second hand replacement. Are there any otehr bikes that use the same caliper as i cant find any for teh cb250 on fleabay.

mr.z · World Chat Champion Joined: 04 Feb 2004 Karma :

If you take a pic i might be able to help.. i'm quite sure its the same on a few bikes, is it twon or single piston?

Whats wrong with the calipers btw?
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mrtEE · World Chat Champion Joined: 12 Sep 2005 Karma :

Its a 2 piston caliper, it only has one on the front. Nissin i think. Its leaking fluid from the seals and the pistons etc are in very bad shape.

mr.z · World Chat Champion Joined: 04 Feb 2004 Karma :

Ahh, i think i know the ones... allthough can't think of a specific bike with them..

I'd suggest going to a breakers and takeing one with you, find out which have them, look on ebay (ones from breakers are generally shit, as they have been sat for a few months corrodeing)

David silvers will do pistons and seals for them, not cheap but if your only haveing one side its not so bad.. you can sand the pistons down in many cases and have them working good (just have to make sure there not cutting into the seals.

Good luck Thumbs Up

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mrtEE · World Chat Champion Joined: 12 Sep 2005 Karma :

heres some pics:

https://i39.photobucket.com/albums/e172/mrteee/Picture029.jpg

https://i39.photobucket.com/albums/e172/mrteee/Picture028.jpg

https://i39.photobucket.com/albums/e172/mrteee/Picture026.jpg

https://i39.photobucket.com/albums/e172/mrteee/Picture025.jpg

mrtEE · World Chat Champion Joined: 12 Sep 2005 Karma :

mr.z · World Chat Champion Joined: 04 Feb 2004 Karma :

TBH yes probably, any seccond hand one you get is likely to be crap, especially from breakers..

personally i'd have the pistons out, get them as smooth as i could and pick out the seals, clean behind them (they corrode behind the seals, which can push them out, with the results you have there) fit new ones lubricateing with some brake fluid and your sorted Thumbs Up

give it all a reeealy good going over with a wire brush and brake cleaner spray (very important to use this), maybe a bit of caliper paint...

There not bad at all them pistons, get the surface rust off and and work down to fine sandpaper, make sure theres no edges sticking out.

Allways be 100% sure with brakes, bodges here can get you killed Sad

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Hotdog · Nearly there... Joined: 28 Sep 2005 Karma :

Brake calipers have a seal between the piston and bore.

This allows the fluid to move the piston and hence the brake pads.

They also have a secondary 'dust' seal that allows the piston to move in and out (normal usage) and protects the piston seal from contamination.

I can't clearly see your outer seals and the inner seals seem to be protruding past the piston.

This usually happens when the piston seals are lubricated with the wrong grease or the outer seal fails and the slot that they sit in gets contaminated and the aluminium furs up filling the slot and pushing the seal out of place.

Hotdog.
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Hotdog · Nearly there... Joined: 28 Sep 2005 Karma :

mr.z · World Chat Champion Joined: 04 Feb 2004 Karma :

If parts are very obviously crap (the pistons) then yeh they need replaceing, ive seen worse than them on prefectly serviceable bikes (not mine mind)

Fitting new pads may push them in far enough to have the jagged piston parts damageing the seals.. new pistons are a good idea if you can afford them, if they are catching theywill just chew up any new seals.

The wirebrushing i mean the caliper body where the dust gets in there..

tbh ive never needed to replace any, so perhaps i'm quite wrong on the procedure.. btw i didn't mean to suggest reuseing the seals Shocked

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Hotdog · Nearly there... Joined: 28 Sep 2005 Karma :

"tbh ive never needed to replace any, so perhaps i'm quite wrong on the procedure.."

Should you really be offering advice at all ?

Do you understand what the outer seals are there for and why they are important ?
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He's a gentleman, a scholar, he's an-acrobat, he's the one and only truly original.......
Hotdog....(Defender of the weak, the poor and the innocent)
He's The Ace - He's Amazing...He's the Strongest... He's The Quickest.... He's The Best!

mr jamez · World Chat Champion Joined: 04 Aug 2003 Karma :

Why are picking apart his posts when what he has posted is spot on? The pistons will probably be fine, to check them properly you will need to measure the outside diameter and check it is within limits, along with general condition. I bought some seals for my NSR caliper for £2.00 and the pistons were £6 each, I can't see them being much more for a CB250. As for cleaning it up, check mr.z's post Wink

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Hotdog · Nearly there... Joined: 28 Sep 2005 Karma :

mr jamez,

I'm not 'picking apart' his posts and his advice is not 'spot on' - unfortunately.

To quote:

mr jamez · World Chat Champion Joined: 04 Aug 2003 Karma :

Apart from that (hence the measuring bit) I can't see any problems.

After seeing the photo though ( Shocked

) its new piston time.

No my NSR caliper was not like that, the dust seals had given up so I replaced the lot just in case.
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NSR 125F > BROS 400 > NC30 > BROS 400 > Trumpet S4 > '97 VFR 750

Hotdog · Nearly there... Joined: 28 Sep 2005 Karma :