does my front sprocket look alright?

Post Reply
User avatar
fishtail
Site Supporter
Site Supporter
Reactions:
Posts: 1048
Joined: 13 Jan 2012, 11:29
Bike Owned: CRM 250 Mk3
Location: derby/leicester border.
does my front sprocket look alright?

Post by fishtail » 27 Jul 2012, 11:38

I've been shafted!! :shock:

Image


Image


any suggestions?

- angle grinder and new drive shaft?

how much life in the sprocket now you reckon?
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong

User avatar
jompy
Forum Ghost
Forum Ghost
Reactions:
Posts: 493
Joined: 03 Jul 2012, 19:55
Bike Owned: MK2
Location: Derby
Re: does my front sprocket look alright?

Post by jompy » 27 Jul 2012, 11:54

Ohh dear ! sproket teeth aren't the worst I've seen by along shot but some tit has welded the lock tab you in place ! You need a grinding disk & a hammer & then if your carefull you may be able to save the shaft

User avatar
knackeredMk1
Super Moderator
Super Moderator
Reactions:
Posts: 4184
Joined: 03 Nov 2006, 17:41
Bike Owned: Modified Mk1
Re: does my front sprocket look alright?

Post by knackeredMk1 » 27 Jul 2012, 12:16

Your bike just gets better and better :o .

I don't think you will be able to save the shaft even if you are really careful with a grinder without at least splitting the cases and getting some more room to work. The previous owner has obviously welded it up for a reason - Which is probably the shaft was shot anyway.

I think you will need to get a replacement and split and rebuild the engine.

There are a few gearboxes for sale on eBay (don't get a Mk1 unless you want closer gearing) at the moment and I have a final drive shaft that will fit as well. Take your time and make a choice before that sprocket wears completly out (it's pretty close and beyond normal replacement) and you are really stuck :cry: .

User avatar
fishtail
Site Supporter
Site Supporter
Reactions:
Posts: 1048
Joined: 13 Jan 2012, 11:29
Bike Owned: CRM 250 Mk3
Location: derby/leicester border.
Re: does my front sprocket look alright?

Post by fishtail » 27 Jul 2012, 12:31

+edit+ oops Kmk1 posted that whilst typing this

and yes I got the best blessed bodge fairy bike ever! :roll: :(

guessing cos the splines have gone on the shaft?

are output shaft commonly available?

I have a cracked case - so I figured I would have a go at cracking the whole thing "one of these days"

altho I'm tempted to ride it lot this year - then do the lot in the "off season " when I wouldnt want to ride it much.
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong

User avatar
fishtail
Site Supporter
Site Supporter
Reactions:
Posts: 1048
Joined: 13 Jan 2012, 11:29
Bike Owned: CRM 250 Mk3
Location: derby/leicester border.
Re: does my front sprocket look alright?

Post by fishtail » 27 Jul 2012, 12:38

seriously I must have got the worst one ever,. :|


I'm thinking I better crack the case and see what else is wrong in there?!! before buying bit by bit...


weekend warrior also a HK'er dropped his engine in 90 minutes last week..

he said the swinging arm bolt wasnt an issue...

no salt on the roads over here.. you reckon thats it?
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong

fallenmikethebike
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 3520
Joined: 02 Dec 2007, 16:02
Bike Owned: MK3
Location: Mid Surrey
Re: does my front sprocket look alright?

Post by fallenmikethebike » 27 Jul 2012, 16:31

:OMG Incredible, possibly, if you can get the old sprocket off, VERY carefully, a thread could be tapped into the centre of the shaft, this could then have a bolt with a large washer on and be used as the retaining method, but getting the old one off, good luck with that project.
A newer chain will prolong the life of the sprocket, but, it's somewhat academic, as you're only putting off the obvious.
Mike
VFORCE REEDS-MUGEN HEAD AND BARREL-WHITE POWER-ALL ON MY WISH LIST!!

User avatar
fishtail
Site Supporter
Site Supporter
Reactions:
Posts: 1048
Joined: 13 Jan 2012, 11:29
Bike Owned: CRM 250 Mk3
Location: derby/leicester border.
Re: does my front sprocket look alright?

Post by fishtail » 30 Jul 2012, 17:14

i'm gonna go in next month I think,

scored a flywheel pull for about 6 pounds in my local shop..

I'm just gonna grind the bodged cog off and get a 2nd hand gearbox

will get cylinder bored out at the same time.. new piston/ rings.

set of bearings etc,... ( I found a cool bearing shop near me - it just sells loadsa of different sized ones,, or do I need honda ones? )


I can powder coat the crank case right? gonna have to google on that - masking the insides / bolt holes and joints?
how about the cylinder head? undecided about this as I prob wont do the frame and stuff since I seem to drop it alot.. :D

but if its not too expensive wouldnt be bad...


but then they sprayed the front forks black - thats rubbign off and looks like they were blue anodised under there.. ( paint stripper wont remove the anodisation right? )
1996 CRM 250 "Mk 3" FMF pipe .... - the other 'un is a 98 hornet 600 - Sai Kung Hong Kong

back off road
Super Moderator
Super Moderator
Reactions:
Posts: 1027
Joined: 12 Sep 2010, 10:48
Bike Owned: KTM 200 exc
Location: Derbyshire/Notts border
Re: does my front sprocket look alright?

Post by back off road » 30 Jul 2012, 17:27

correct on removeing the anodised finish ;)
Im thinking about a bike with more valves than a powervalve

User avatar
knackeredMk1
Super Moderator
Super Moderator
Reactions:
Posts: 4184
Joined: 03 Nov 2006, 17:41
Bike Owned: Modified Mk1
Re: does my front sprocket look alright?

Post by knackeredMk1 » 30 Jul 2012, 18:50

You can powdercoat the cases the barrel and the head but you have to take the bearings out.


Post Reply