14 T Sprocket for 848

[Aran]

I tried to search the site for this subject in case it had already been discussed but I didn't come up with anything. My question is to anyone with an 848 who has swapped out the front sprocket for a 14 T sprocket. Specifically, was it a worthwhile change? What made you do it in the first place? Were there any unforseen consequences of the change? I just bought a new '08 and I'm wondering if I should have the dealer make the change before I take delivery in the spring. Any help you can offer will be appreciated.

Aran

[Tonto]

Does it come with a 13 standard? (can't remember). Be careful with the front sprocket as 1 tooth either way up front is like 5teeth in the rear. You'll notice a far more dramatic difference in gearing (good OR bad) playing with the front. I did the back on my 749 by three teeth and found it to be a lot more agressive on the jump at the sacrifice of a little top end (big deal, I'm not racing).
TONTO

[Aran]

Thanks Tonto.

I believe the stock sprocket is 15 t. I've seen a lot of guys from the U.S. say the swap does great things for slow speed rideability and acceleration and with no real drawbacks.

[darnold]

Changing the front is cheaper then the rear. Changing the rear may require a new chain and a ride height adjuster. Things to think about.

Back to the ratios, my 848 with standard gearing would pull six gear to just over 9k rpm on the Mosport straight. This is not the red line and is 253kmph indicated. At Calabogie i never used 6th gear at all.

I would think that one less tooth on the front would make it a better street bike and it's a low cost change. For the track smaller steps on the rear sprocket would be better.

You should ride it yourself so that you really understand the changes and the results. Makes a more interesting experience.

[Ken L]

I change a lot of my customer 848s to 14 T fronts. Big improvement in general, no complaints!

[Tonto]

interesting discussion, and good points by all. Its true, at the track with my kid's RS, pulling the pinion sprocket is way faster than removing the rear wheel and is not as drastic a difference to compensate for with regards to the chain length.

Tonto

[Aran]

Thanks for the input guys - very helpful.

darnold:

I agree that it makes sense for me to ride the bike stock before I make any changes if for no other reason than to fully appreciate the benefit once the change is made. The dealership isn't just around the corner so convenience was a consideration in having the new sprocket put on for delivery but there's no denying that part of the enjoyment of a bike is making changes and evaluating the effect. Without riding it stock for a while I'll have no baseline.

Ken L, Tonto, and darnold:

Am I correct to assume that from your comments none of you think a new chain is required with the 14 T?

[Tonto]

I'm pretty sure that there is enough movement of the eccentric to allow for the install of the front sprocket without loosing a link or two. The only caveat being that if the bike is brand new, the chain has yet to be stretched and the tension readjusted. I know I had the chain replaced when I did the rear on the 749 (it was due anyway and was not a significant cost when applied to the whole mod). The dealer can tell you for sure if the chain needs replaced. By the way, keep the old one, after all, its new!

Tonto

[Mike_D]

[Aran]

Thanks again guys, you've been a great help. I'll let you know in the spring how it works out.

Aran