Reduction gear from Apex to RX?

[MSRX-ERNIE]

Does any one know if the reduction gear from the Apex will fit in a RX?
If it does will there be any gain in speed or other benefits/downsides?

I was thinking if it fits the RX propably will be a bit faster, maybe even be able to keep up with the Apex?

I know the Apex engine have more rpm´s in top but it´s not that much is it?

Ernie

 

[nhrxrider]

It would take a lot more than gearing to make an RX keep up with an Apex. Having been lucky enough to have ridden one, the Apex is lighter, it has more HP, and it hooks up way better. Any one of those things makes a big difference. Count all 3 together and a stock RX has no chance, even if it has slightly different gearing.

As far as gearing, I'm not 100% sure, but I think the RX uses the same type of gears as many other Yamahas, so I think changing the gearing should be easy. Depending on where and how you ride, that alone could make a HUGE difference in performance. For an example, I used to live in an area with mostly tight, twisty trails. Very occasionally we would get out on a small pond or lake, but most of the time we never got above 60 mph except for a short burst on a railbed trail. So on my ZRT-800, I installed 440 gearing in the chaincase, and man, what a rush that was to ride!!! NOBODY could keep up with me off the line, or up to 80 mph for that matter. Holeshots were instant, and I had arm-ripping power out of the corners. The downside was out on a lake, where my top speed was only around 95 mph. But for the 3 times a year I got on a lake, I didn't care because the rest of the time made up for it. And not only was the performance improved, but because the belt didn't have to slip as much in the slow sections, belt life increased. And because the engine had an easier time getting the sled moving, I actually noticed a slight increase in economy.

Sleds come out of the factory as a compromise. We need to tailor them to fit our individual needs. The guys on the lakes play with turbos and higher gearing, guys in deep woods and tight, twisty trails get to lower the gearing for a better overall feel and more low-speed power.

Jim

 

[Srxspec]

I believe he is talking about the gear reduction from the crank to the pto shaft that drives the clutch. The Apex has a higher reduction to bring the engine rpm of 10,500 down to 8450 at the clutch like the RX-1 has.

 

[Tork]

One of them was 31/37 I think. Anyway I seem to remember it changed by one tooth.

 

[Srxspec]

RX-1: 31/37 for a 16.3% reduction

Apex/Attak: 30/37 for a 19% reduction

 

[MSRX-ERNIE]

I believe he is talking about the gear reduction from the crank to the pto shaft that drives the clutch. The Apex has a higher reduction to bring the engine rpm of 10,500 down to 8450 at the clutch like the RX-1 has.

You are absolutely right! So is it possible? Any benefits, downsides??

Thanks

Ernie

 

[Srxspec]

For a trail application I see no gain in switching it in your 03-05 RX. You may see a little more torque on the dyno, but I doubt you'd even notice it out in the field.