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30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 10:49 pm
by Neosophist
Since I now have my forks and clutch system sorted out for the 24 i'm starting to focuson the rear now :scare:

My original plan for the rear was to a the VFR750 wheel with the use of spacers to avoid hitting the chain and move the linkpipe a tad.

However, I was looking at a 30 hub assembly today and i'm sure it'll fit straight into the 24 swinging arm as it looks practically identical, but if not I can get a complete NC30 rear-end for pennies, with hub / shock too ^_^

While converting it to a 30 style rear would be one way to go i'll loose the cush-drive of the 24 :(

Both are gonna cost me pretty much the same in the end, does having the lack of cush-drive on the later models affect the wear and tear rate much? ie chain / sprockets / wheel bearings? as from my understanding the cush-drive is there to reduce stress by acting as a dampner.

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 10:52 pm
by CMSMJ1
Yep - the chain on a 30 takes a beating but I feel that it cannot be that bad. a 525 size on a bike this small must be decent enough.

It may be, for a shot in the dark, that the sprag clutch lessens some of the absloute shock loads the chain would have with no cush drive.

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 10:58 pm
by fastdruid
I wonder if part of the reason is that the NC24 is 180degree while the NC30/35 are 360degree.

Druid

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 11:34 pm
by Neosophist
fastdruid wrote:I wonder if part of the reason is that the NC24 is 180degree while the NC30/35 are 360degree.

Druid
Interesting... hadn't considered that train of thought. The 24 also has a 525 chain so i dunno why it was left out of the 30/35 model.

It doesn't weigh all that much and considering i'm no rossi (as you'll probably find out on the next 400 trackday :D) I might just leave it there and go the original plan of the 750 rear wheel.

thanks for the suggestions... does no one else have anything cooking atm besides me? :(

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 11:45 pm
by Cammo
The nc30/35 has a sprague clutch that acts as a kind of slipper clutch, this may reduce the wear of not having a cush drive. Does the 24 have this?

Chain wear is not too bad on the 30 imo (it does take some punishment though), but if left unattended will reduce the life considerably. Same as any bike I guess.

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 11:50 pm
by fastdruid
Neosophist wrote:thanks for the suggestions... does no one else have anything cooking atm besides me? :(
Er yes but not for a 400.

Actually more a simmer atm because of the 400's really.

I've bought more bits for my RC24 project[0] and thanks to Zimm I have a nice programable CDI for my SV650/700 on-going project[1] but the 400's are pretty standard. Well apart from the carbon fibre bits anyway!

Actually I suppose the NC24 frame looks rather like the RC24. :D

Image

Druid

[0] I'm putting a CBR600RR5 rear end and R1 frontend on it.
Have all the bits for the rear end, just need R1/R6 calipers, a front wheel/discs, a mudguard and some kind of remote res clutch master cylinder. Then a bit of time on a lathe...
[1] USD forks, 6 pot calipers, alloy subframes, GSXR fairing, OSF rearsets, akrapovic exhaust, lots of crash bungs...

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 11:53 pm
by fastdruid
Stickshift wrote:The nc30/35 has a sprague clutch that acts as a kind of slipper clutch, this may reduce the wear of not having a cush drive. Does the 24 have this?
A sprag clutch is a one way clutch typically used for the starter. I'm pretty sure the NC30/35 doesn't have one in any other function.

http://en.wikipedia.org/wiki/Sprag" onclick="window.open(this.href);return false;

Druid

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Tue Oct 21, 2008 11:54 pm
by Jon
fastdruid wrote:I wonder if part of the reason is that the NC24 is 180degree while the NC30/35 are 360degree.

Druid
The 180 degree firing split will be easier on the chain than the 270/90 degree split of the NC30/35 as it is more even.

The slipper clutch only has an effect under engine braking and no effect when powering on.

regards
jon

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Wed Oct 22, 2008 1:31 am
by Neosophist
fastdruid wrote:
Neosophist wrote:thanks for the suggestions... does no one else have anything cooking atm besides me? :(
Er yes but not for a 400.

Actually more a simmer atm because of the 400's really.

I've bought more bits for my RC24 project[0] and thanks to Zimm I have a nice programable CDI for my SV650/700 on-going project[1] but the 400's are pretty standard. Well apart from the carbon fibre bits anyway!

Actually I suppose the NC24 frame looks rather like the RC24. :D

Image

Druid

[0] I'm putting a CBR600RR5 rear end and R1 frontend on it.
Have all the bits for the rear end, just need R1/R6 calipers, a front wheel/discs, a mudguard and some kind of remote res clutch master cylinder. Then a bit of time on a lathe...
[1] USD forks, 6 pot calipers, alloy subframes, GSXR fairing, OSF rearsets, akrapovic exhaust, lots of crash bungs...
Aah.. that rear-end looks like the gullarm rear-end.

as for the NC24 frame...

Image

Quite similar I thinks..

-edit-

bored much...

Image

Oh and while i was browsing some specs earlier came across this...

VFR400R(NC24) Overview : Change rear swing arm to PRO-ARM.
(Apr,'86) Max. H.P. : 59PS / 12500rpm
Tolque : 4.0kg-m / 10000rpm
Size : 2010mm(D) x 690mm(W) x 1125mm(H)
Wheelbase : 1375mm
Dry weight : 164kg
Front wheel : 100/90-16 54H
Rear wheel : 130/70-18 63H
Price : 679,000yen ($7,988)

VFR400R(NC30) Overview : The first model of NC30. All parts are
(Dec,'89) renew. With 360 degrees crank.
Max. H.P. : 59PS / 12500rpm
Tolque : 4.0kg-m / 10000rpm
Size : 1985mm(D) x 705mm(W) x 1075mm(H)
Wheelbase : 1345mm
Dry weight : 182kg
Front wheel : 120/60R-17 54H
Rear wheel : 150/60R-18 67H
Price : 695,000yen ($8,176)

VFR400R(NC30) Overview : Suspention changed(front/rear)
( ,'91) Max. H.P. : 59PS / 12500rpm
Tolque : 4.0kg-m / 10000rpm
Size : 1985mm(D) x 705mm(W) x 1075mm(H)
Wheelbase : 1345mm
Dry weight : 185kg
Front wheel : 120/60R-17 54H
Rear wheel : 150/60R-18 67H
Price : 719,000yen ($8,459)

20kg lighter!! 8-)

Re: 30 / 35 riders, lack of cush-drive question.

Posted: Wed Oct 22, 2008 2:08 am
by Cammo
fastdruid wrote:
Stickshift wrote:The nc30/35 has a sprague clutch that acts as a kind of slipper clutch, this may reduce the wear of not having a cush drive. Does the 24 have this?
A sprag clutch is a one way clutch typically used for the starter. I'm pretty sure the NC30/35 doesn't have one in any other function.
It does use one in the clutch function.

Not typically a true slipper clutch by todays standards, but like Jon said it eases pressure on teh clutch under heavy engine braking.