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Discussion Starter #1
Hi All, what sprockets should i use for my 72 tiger 650 with a 750 kit, i will just be using it around town with the odd 100 mile trip, any input appreciated thanks
 

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Hi All, what sprockets should i use for my 72 tiger 650 with a 750 kit, i will just be using it around town with the odd 100 mile trip, any input appreciated thanks
ecose,

Wow that was really an open ended question.

I know the bike's weight, how about your weight?
Plan on two up riding?
Saddle bags?
Side car?
Around town, is that 30mph 40mph 50mph?
Trips are those secondary roads or Interstate driving?

Ok as for all of that here is what I got running.
1979 750 5 speed, not 5 speed and 4 speed have the same
top gear ratio.
Bike's dry weight, 395lb my weight 169lb ( and getting lighter)
No two up riding, Saddle bags sometimes. Side car is a big
no.
Around town is average 40mph, some interstate driving at
around 70mph.

I have a 20 tooth front sprocket and a 43 tooth rear sprocket.
It will depend on if your sprocket is part of the drum brake or
not on what tooth counts are avalible for your model

And remember, more weight you will have to gear down. That
is a lower number of teeth on the front sprocket or a higher
number of teeth on the rear sprocket. And of course lighter
weight is the inverse.

Pookybear
 

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Discussion Starter #3
sprockets

ok, 150lbs, no baggage, no passengers or sidecar, 30-50 around town with the odd 70mph hywy, its a 4 speed with stock 19 front and a 47 rear, i just wondered if others have had experienced better results with
an 18 front or???
 

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Why would you want to go from a 19 tooth to an 18 tooth front sprocket unless you want to do some street drags at the stop lights? An 18 tooth sprocket on the front is pretty much comparable to adding two teeth to the rear. It will gear you down by better than 5% so you will be red-lining and shifting sooner. With a 750 kit you have more power than stock. You're not overloading your bike.
If any change, most riders would be looking for taller gearing.
 

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hi ecose,
leave the front as it is (more work to change) try going down a few teeth on the rear, that will give you less revs for the same speed but won't be too different in pick-up
 

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ok, 150lbs, no baggage, no passengers or sidecar, 30-50 around town with the odd 70mph hywy, its a 4 speed with stock 19 front and a 47 rear, i just wondered if others have had experienced better results with
an 18 front or???
Ecose,

Thirdbike is right you got that backwards. You would want to
go up on the front and down on the rear for more speed with
less rpms.

With as much weight as you carry, you could try out two
different types of gearing right off the bat.

You can work with either the front or the rear. Now the front
mean that you have to remove the primary and the clutch just
to get to the sprocket. This is a good way to go if either you
are having clutch issues or you are leaking oil around the front
sprocket area. If not work with the rear sprocket first.

So the basic rule applies. you have a stock 47 tooth unit so
again it depends on what kind of set up you have if it is a bolt
up sprocket or if it is part of the drum, I do not have your bike
in front of me so you would have to tell me.

Rule states. more speed less rpms for the rear sprocket the
number of teeth goes lower. Less speed and more rpms the
number of teeth goes up.

So for your basic driving you most likely would like either the
45 tooth or a 43 tooth unit if availiable.

If you do have clutch problem or a leak around the front sprocket
the other rule applies.

Rule states, more speed less rpms for the front sprocket the
number of teeth goes up. Less speed and more rpms the
number of teeth goes lower.

So for your case a 20 tooth on the front would be a great bolt in
job. This will act like a two tooth change on the rear of the bike.

I hope this helps out a bit and does not confuse you.
If confused, write back,

Pookybear
 

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Discussion Starter #7
sprockets

hi, thanks for all the info, i am in the middle of a complete rebuild so now would be a good time to make a change, given the difficulty in changing the front i was thinking of stock on the front and playing with the rear bolt on 47 tooth rear, maybe start with a 45? i have never ridden this bike or one like it, i bought it and tore it apart right away
 

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hi, thanks for all the info, i am in the middle of a complete rebuild so now would be a good time to make a change, given the difficulty in changing the front i was thinking of stock on the front and playing with the rear bolt on 47 tooth rear, maybe start with a 45? i have never ridden this bike or one like it, i bought it and tore it apart right away
What a complete rebuild. Well if you are doing that you will
be doing a clutch job in there somewhere. That is the time
to do the front sprocket. I would start there if you are doing
the rebuild. The rear you can do anytime. Go for the 20 tooth
on the front.

Just my advice, you can take it, you could listen and make up
you own mind or you could just say I am nuts and do your own
thing,

Pookybear
 
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