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Discussion Starter · #1 ·
I installed the Rhinewest cam sprocket/chip kit on my K12rs last week. Fattening the torque curve down between 3500/6500 RPM totally changed the character of the bike. I pulled out to pass a slow moving truck on my first run and it spun up so fast I thought I had left it in second gear!

Side benefit - the 3500/4000 RPM buzz is gone.
 

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Tell us more

What year is your bike? I understand Rhinewest recommends keeping your stock exhaust, is that right? Any other observations, tips, etc?

Thanks for the info.
 

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Discussion Starter · #3 ·
More Rhinewest

The bike is a 99. You are right about the stock exhaust - I found one on line for $100 + shipping.

If you have ever adjusted your valves you will not have any problem with the install. One tip I will offer is to mark the teeth on the spockets and the correponding side link on the timing chain when you have the motor at TDC, BEFORE you take off the factory sprockets. I cleaned the oil off of the face of the sprocket and the side links of the chain and used a permanent marker. Mark the new sprockets at the same spot so that the chain engages the sprocket teeth in the same place.

Plan on spending the whole afternoon in the garage!
 

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It sounds like you had an aftermarket exhaust on it before. Is that correct?

If so, which one and what is your opinion of the aftermarket exhaust vs. the sprocket kit?

I like the look of the aftermarket exhausts and the weight savings, but not the sound when just running around town (when really getting on it, the throatier the better!). So, I have stuck with the factory for now. Getting the increased performance while keeping it quiet for the neighborhood and cops sounds like a real winner!

Randy
 

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Discussion Starter · #5 ·
More Rhinewest

I did not have an "aftermarket" exhaust. I had improved the breathing and reduced the backpressure of the stock exhaust by removing the catalyst. It did not noticably increase the noise.

I already had a Rhinewest chip in the bike and I cannot say that I noticed a big difference with the open exhaust. Since I did not benefit from the reduced weight of an aftermarket exhaust I decided to go on a diet which has been very successful in reducing my overall sprung weight anyway.........

The differnce in performance between the open exhaust with the chip and the sprocket kit, (which comes with a new chip) is remarkable. The sprocket kit wins hands down.

A side note... the engine now has a noticable "growl" that it did not have before.
 

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Thanks for the feedback!

It sounds like the sprocket kit is the ticket!

Randy
 

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Thanks for your report. The claimed gains look quite dramatic and exactly where I would want, in the low to midrange torque whereas a lot of performance exhaust will often show some loss of low to midrange torque. I surprized we have not had more chatter here about this upgrade.

What exactly do the new sprockets do? Do they subtly change valve timing?
 

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Discussion Starter · #8 ·
More Rhinewest

Yes - The Rhinewest sprockets change the valve overlap by slightly shifting the pin that locates the cams on the sprockets.
 

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QUESTION: Have you had time to see if your gas mileage is changed with this kit ?

Thanks,
 

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Discussion Starter · #11 ·
Rhinewest mileage

I have only had time to run two tanks through it so it is a bit to soon to tell.

With that in mind.... up to now my low fuel light typically comes on at 132 - 137 miles. The last tank the light came on at 147 miles.... I was on a two lane road stuck in 60 MPH traffic, which is not my normal riding style.
 

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Thanks for the info about the gas mileage (up to now).

Please keep us up-to-date as the mileage increases.
 

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Can you post pixs of the OEM with the Rinewest sprockets together along with their specs(measurements and/or # of teeth diff.). Trying to vizualize the Valve overlap vers. valve duration which is only associated with cam lobe regrinds
 

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If you have any K1200RS riding buddies, I'd be real interested in a roll-on comparsion in 6th gear.
 

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Discussion Starter · #15 ·
aa3jy said:
Can you post pixs of the OEM with the Rinewest sprockets together along with their specs(measurements and/or # of teeth diff.). Trying to vizualize the Valve overlap vers. valve duration which is only associated with cam lobe regrinds
I do not have the spec's, you might ask Rhinewest. The new sprockets are in the bike so the photo op has passed. The intake / exhaust valve overlap can be adjusted because the intake cam and exhaust cam are separate. The sprockets have the same number of teeth, they simply change the postion of the exhaust cam relative to the intake cam by moving the locating pin - you can see the pin in the photo that rickd posted on Nov 27th. There is no change in the valve duration.
 

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Discussion Starter · #17 ·
Rhinewest Sprockets

brentboshart said:
If you have any K1200RS riding buddies, I'd be real interested in a roll-on comparsion in 6th gear.

I plan on that - unfortunatley my buddy has no Gerbing gear and my chances of getting him out for a run before spring up here in Washington are slim! -
 

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