Hi All,

Been a fair while since i frequented this forum - that long that I have forgotten my old user / pass. Used to have a '30, but sold it about 6 years ago - still wish i'd been able to keep the old girl, but needs must and all that. From what i remembered, this was a helpful and very knowledgeable forum, so i thought i'd come and ask some questions.


Aaaanyway, on to the topic at hand. I've bought myself a 21 as winter transport, as it's killing me riding my zx6 into work every day, and the other half is itching to learn to ride, so i've basically said she can use it when i get her back on the road.

I'm currently in the middle of getting her prepped for MOT, fixing any bodges that have been done in the past, and generally geting the gal back in to something resembling decent form. Things have been going fairly well, unfortunately i think the collector box is thoroughly knacked - mainly cause its currently covered in what appears to be gungum or similar, but thats something 110 quid should fix. Am i correct in thinking that you have to drop the engine to fit the rear downpipes / collector box?

My main issue is about the front brakes, the pad coverage on the disk to be precise - are they supposed to only cover about 3/4 of the disk width? Never seen anything like it before, but as i've not owned a 20 year old bike, i guessed it could be related to that. It appears to have the correct pads in, but it was something i'd rather check than risk.

Also, in regards to this, the LHS caliper has had a 5mm groove cut in it between where the pads sit - its clearly been cut by the edge of the disk itself - although there's no obvious sign of damage / rubbing on the disk edge. Clearly this isnt right, and it doesnt appear to be doing it now, but has anyone ever seen anything like it before?

Thanks

Dale

Hiya.

Yes, engine has to come out to fit the collectorbox.

Good news is that you can still get NC21 collectorbox if your lucky.

The brake pads make full contact with the disc, maybe something isn't sitting right. If you want i'll photograph my discs / brake caliper set-up as they were only rebuilt 2 months ago.

http://www.dunc.freeuk.com/bikes/nc24/engineindex.htm" onclick="window.open(this.href);return false;

You will want to follow the above to remove your engine. ^^

Maybe there has been a different caliper fitted? The LHS is connected to the anti-dive so the mounting is different.

Do you have STD discs on there? NC21 has non-floating 276mm discs.

Hey Neo,

Thanks for the reply - i've been scouting around here today, and from what i've been reading it seems you're one of the resident 21 / 24 experts - i was kinda hoping you'd reply!


Hmm, maybe i've explained it badly.... the pads themselves appear to be making full contact with the disk - its just that the pads themselves are'nt deep enough to contact the entire disk surface / depth - I'll have to get a couple of images myself of the disk and the damage to the caliper - i guess it will probably be quicker and easier for you to see the disk/caliper+mount on mine rather than me try to guess at it!

I wondered what the contraption was fitted to the LHS fork, but had a look at some photo's online and managed to figure out it was supposed to be like that! I know it was a young lad that had the bike before me, i've already found a bodged pad retaining pin in the other caliper, so it may be that it's been fitted incorrectly at some point. Anti-Dive eh? Yet another relic from the past! I'll be refreshing the fork oil before she goes back on the road - i assume from what i've read of other systems, that this will mean that the anti-dive is still totally useless? :)

The caliper itself looks identical to other's i've seen, but I wouldnt be sure, and i've been at work all day today, so its not something i can go check at the moment.

As far as the disks go, i think they're standard, as they match what i've been seeing around, but without a tape measure and the bike handy, i cant tell you atm.

In regards to the collector box, i thought i had read that somewhere. That's a bit of a pain in the arse, but one of those things, i guess... I had a look at the David Silver website today, and they appear to have the collector and downpipes for about 110 quid. Not sure if they're stainless or not...... Thanks for the link- i've had a quick read through and it looks fairly straight forwards. I remember the NC30 being a pain to work on, so i guess i shouldnt expect this to be any different!


Thanks again for the reply,

Dale

Ok then, i have some photo's - just quick ones, but hopefully you'll be able to see something - a 13 hour shift on a sunday makes you lazy!

And yeah - i know the disks are in a state - they'll be coming off for a clean.

Ok then, I've marked the area the pads are contacting - in case it wasnt overly visible.

The RHS - from what i can see, the "normal" side:


The LHS - the side i think is iffy:


And finally, the iffy caliper - i've highlighted the grooves that the disk has cut in it. As i said, there's no sign of damage / rubbing to the disk itself, which is a little confusing......

Ok those are NC24 discs are there floating.

NC21 discs look like





The anti-dive isn't useless. When you brake hard it presses a little pin into the forks to slow the compression rate of the forks down to help prevent bottoming out.

If your used an an NC30 you might find the forks a little soft.

I see what you mean, my NC24's are the same with the last bit of disc being unused.

It's not noticable on clean discs, if you have a noticable ridge your discs might be badly worn? The discs are pretty much bullt proof though unless you use them without brake pads >.<

All I can presume with the left hand caliper you have pictured is that somebody has tried to bodge some wrong' pads in it at one point.



^ Standard pad dimensions

The collectors from DSS are Genuine honda ones, hence Mild steel. If your serious about keeping the bike get one asap. There hard to get hold of as NC24 owners are buying them and modding the exit pipe to fit, as the 24 one is harder to get.

I can't see which side that is, if it's the LHS is it possible it'd had an anti-dive bearing failure some time in the past and moved enough to touch it?

As for the anti-dive, it works in that it causes the 750 to skip the front on the brakes when it gets bumpy...

Druid

Neosophist wrote:Ok those are NC24 discs are there floating.

Believe it or not, in 10 years of riding, i'd never seen a pair of non floating disks...... I knew the difference, but hadnt seen a set of non floaters!

The anti-dive isn't useless. When you brake hard it presses a little pin into the forks to slow the compression rate of the forks down to help prevent bottoming out.

If your used an an NC30 you might find the forks a little soft.

Ok, well, that makes sense, Im used to a very stiff setup on my '01 ZX6R - so yeah, they're very soft next to that, but tbh i expected them to be - the thing that surprised me most was the seat to peg dimension - they feel very tight.

Thanks for the pad dims - will do some measuring tomorrow.... i dont think theres a particularly big ridge - definitely not on the rhs one, anyway. Thanks for the info on the DSS downpipes - is it worth waiting to see if i can get hold of some SS ones? I'm definitely keeping the bike though.

fastdruid wrote:I can't see which side that is, if it's the LHS is it possible it'd had an anti-dive bearing failure some time in the past and moved enough to touch it?

As for the anti-dive, it works in that it causes the 750 to skip the front on the brakes when it gets bumpy...

Druid

Yeah, its on the LHS - not sure on the gubbins that sits in the anti dive, although i can understand how that could happen. I take it the mechanism is replaceable?


Thanks for the input guys.

Dale

You can't get SS pipes unless you have some made.. the DSS ones will be ok, afterall the ones on there now have lasted over 20 years

Ahh, i guess this is true - good old honda engineering :)

Is there any way i can check if the anti dive mechanism is damaged?

Well, i have thursday / friday off this week, and apart from the new rear tyre i need to get fitted to the 6, and the sky engineer that's coming on thursday to replace my knacked 3 month old sky box (grrrr), this is all i have on the schedule.


All good fun!