Odometer question

[JohnD]

Hey folks

Finally got round to fitting my +2 Tooth rear sprocket yesterday

Now I realise this will put my speedo out a bit, but what about the odometer will this be affected (i.e. is it measured at the same place)?

Thanks

John

[Stratman]

As far as I know the answer is, yes it will.

[kevg]

have a look on ebay for speedo healers, that should sort it out. i'm sure there are a few folk on here got them and can give you advice.

[Pete.L]

John said

Now I realise this will put my speedo out a bit,

Never mind That!!!
What do you think?.... Have you pinned it yet?

Pete.l

[JohnD]

John said

Now I realise this will put my speedo out a bit,

Never mind That!!!
What do you think?.... Have you pinned it yet?

Pete.l

Good man!! Straight to the bit that we really want to know about Sod the speedo, is it good fun to ride?

LOL - yeah sorry I neglected the important bit eh!

Had a good blast on it on sunday... & yes it's a great mod! Acceleration is loads better, front wheel comes up much easier than before, & it handles better too (as wheel base is shortened). Only downside is that I found I was dancing round the gearbox more than before... but am sure i'll get used to that!

[balls]

Hi there
I would like this to do this mode as well as the bike is a pain to ride slowly around town and top gear feels to tall , Where did you get your sprocket from and how much was it.
All the best Neil/balls

[JohnD]

Hi

Got my sprocket from wemoto for around £25 inc postage i think

http://shop.wemoto.com/index.dyn?oid=25299

(see chain & sprockets section about half way down)



John

[JohnD]

Oh yeah, in case anyones interested, I worked out that my odometer is overreading by around 4-5 miles every 100 which I can live with !

[bandsawman]

I was told that the usual mod to do on these was to go down one tooth on the front (and that'd only cost about £6)?

[tony.mon]

Right enough, but it wears the chain out a bit quicker.

[jambo]

Right enough, but it wears the chain out a bit quicker.

what about one down on front and one up on back?
read that it is good for the cct's,is this true?

[mwross1964]

yeah prey tell someone!
save puttin on manual (as ape)

[Pete.L]

Right enough, but it wears the chain out a bit quicker.

what about one down on front and one up on back?
read that it is good for the cct's,is this true?

I think you can throw that idea in the "wishful thinking" bucket

Pete.l

[tony.mon]

Agreed.
The point about the chain wear is that you're asking the chain plates to bend a wee bit more relative to each other each time they run round the front sprocket, as the diameter's smaller.

It's the smallest sprocket that affects this, the bigger one has much less effect on the angle that the plates are to each other, assuming that the teeth are in good condition.

But the rear one wears the chain in a different way; with the larger sprocket, the more links are in contact with the sprocket at any given time, and as the chain wears it puts sideways pressure on the tooth profiles- that's why an old chain fitted to a new sprocket knocks it out in double quick time.

I can't see any advantage to the CCT's- all that will happen is that the gearing change means that for a particular road speed you'll have slightly different revs.

Now this would be good for the CCT's and cam chain wear if your revs were lowered all the time (although there are effects elsewhere- increased cush drive wear, gearbox wear), but in practice all it means is that you'd change up or down a bit sooner or later to compensate.

It's really only flat out in top that you'd see a permanent difference; the rest of the time you're going up and down gears and up and down with the revs all the time you're riding.

Standard gearing: 16/41 = reduction of 2.5625:1
Your option : 15/42 = reduction of 2.8:1
popular option : 15/41 = reduction of 2.7333:1
larger at rear : 16/43 = reduction of 2.6875:1 (but longer chain probably needed)

You choose!

Lastly, it's worth mentioning that there's only so much clearance with the chain run to the exhaust pipe as it runs from right to left beneath the bike.
Fitting bigger sprockets both ends would mean that the chain starts fouling it.

God. you can really get anal about this stuff, can't you?