Front Sprockets ? Chain Size

[Dig50]

I need some clarification, that my dealer is not seeming to give.
1) True or False: Does the 18t sproket from an 04 Sprint St fit the 05??

2) True or False: Is the stock Chain on the 05 Sprint ST a 530 pitch?

3) Has anybody done a 18t sprocket in the front AND a 43t in the rear of an 05 Sprint ST??

[DaveM]

Where are you Stlakid,
this is your kinda question.

sorry mate dunno. I run the 18 and 43 on my Sprint '04. Luv it! (thanks again Donski)

I didn't know chains had a "pitch" and dunno if it all fits the same on an '05.

My guess is yes it will but someone else here with your model will know for sure.

DaveM

[BazzaST]

Digi50

Answer: 1 yes

2 yes
As for 3 left the rear on 42 works really fine, great quick take-offs, even great on the highway, no problems.

My 05 Sprint runs 18/42, the 18 tooth sprockets is common to other Triumphs eg Daytonas, Thunderbirds etc.

Barry

[RexxyPup]

Dig 50.

the gearing for the - 04 ST changed over time. One site shows the following

1999 - 18 Front / 43 rear

2000 and up - 19 Front / 43 rear

Certainly my 04 HAD a 19T front!!

They also included a useful table of theoretical speeds for gearing

Front Back Ratio 0-60 0-100 top
19 43 2.26 4.06 8.45 166*
19 45 2.37 3.61 8.44 158*
18 43 2.39 3.59 8.41 157
18 45 2.50 3.66 8.23 150
17 43 2.53 3.64 8.20 149
17 45 2.65 3.54 8.27 142

* Speed at max revs. Wind resistance limits actual max to ca. 157 mph.

You can find the full info at...

Triumphnet.com FAQ

Rexx

[ This message was edited by: RexxyPup on 2007-01-04 11:36 ]

[DaveM]

Rexx,
you are correct 19 is standard on the '04 model.
But it is a bit overall tallish in my opinion that way.

With the 18 and 43 I think it is perfect for my type of riding anyway.

DaveM

[Dig50]

Ok so I would have to go back to a 1999 sprint to get 18t sprocket.
I waiting for a return e-mail from Vortex sprockets on the rear, they have a 43t sprocket that is shown for the 05 ST BUT the web site shown fitments for a 525 pitch chain, not the stock 530. By the way DaveM this is where I picked up that pitch terminology.
Really can anyone break that down, When it come to chain size, pitch, or what ever, I am infantile. All I do know it has something to do with the chains tensile strength(?).
Come on Brainiacs I know your out there Ive read your posts!

[DaveM]

Dig,
try a search here I know there is a decent thread with a bit more techo bumph. Stlakid and Don know all about that sprocket stuff,

I know the kid has a part number and everything.

It has definitely been covered here somewhere.

DaveM

[a1samurai]

Dig50,

The chain picth is the distance between 3 links. A quick look at the EK chain site to refresh my memory shows, that all "500 series" chains have the same picth 15.875mm, but the width shall vary.
A 525 chain will have a picth of 15.875 and a width of 7.94mm, while a 530 chain will have pitch of 15.875 and a width of 9.53mm.
Now the width is to the inside of the chain between the end plates, so if you have an o-ring or x-ring chain the outside width will vary.

When you are changing sprockets, it is best to do when you need everything is worn. It best practise to replace both sprockets and the chain at the same time, to prevent any extra wear.

Also, if you want to drop a tooth on your front sprocket, consider going up on the rear instead. This will help with any premature wear as the chain does not have to rotate around a smaller diamter on the front sprocket. A 45T-46T rear sprocket would be about the same as a dropping to a 18T front.

Sorry for the length, but hope that helps

[hootieST]

Hope I'm not stealing your thread Dig50.

I'm considering changing the rear sprocket for a 45 or possibly 46 tooth. Will I need to use a longer chain??

Cheers,
Mark

[Mr2U]

The 19 tooth stock front is huge,

i have other bikes that run 16 and 17 fronts

Going to an 18 will not cause premature chain wear.


I run an 18 front with the stock 42 rear on my 06'
gives alittle quicker response in the lower gears,
and still loafs along at 80-90 in 6th gear.

i spent more on the 36mm socket to get it off,
than i did on the sprocket.



[ This message was edited by: Mr2U on 2007-01-05 18:17 ]