Close Ratio Gearbox or not

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Feb 26, 2008
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Hi, I am about to order a new gear cluster for my box, and am wondering wheather to go for a close ratio set from RGM or a set of the standard ratio ones, there is not much difference in price. Has anybody used the CR set and what difference can I expect?. My riding is mainly out of town, ie sunday rides with a few friends and a bit of touring, with the occasional bit of round town running.

RGM close ratio

Hi Graeme
My friend John has these in his sprint bike had to lap one in. They have performed faultlessly which was not the case when he tried a reverse cam plate from the same source. Closes up the gap & if you have to buy new why not.
Why not?
Compare the 1st gear ratios.
The difference is the proportion of torque you lose in traffic.
Original 1st gear (example only): 2.6:1
Close ratio 1st gear (example only): 2.0:1
Difference: close ratio 1st gear is 77% of the original, so your 828cc engine feels like a 637cc engine. Also requires more delicate operation of the clutch, etc.
Most of us have got used to running with what is effectively a three-speed gearbox :)

The RGM sets are nicely made.

I think that the decision needs to be based on whether your touring is two-up with luggage, how hilly the terain is and what final drive ratio you'll be using.

First is really just a pulling away gear on the standard box. I don't think that I ever intentionally change down to first if I'm not intending to stop.
Guessing from the RGM page, their close 1st gear is 1.78:1 vs. the stock at about 2.56:1.
If you never go below 40 mph it's fine.
Considering the large number of gear pairs that were offered at one time, I'm surprised that someone hasn't made a better street compromise with a near stock 1st for traffic, big jump to 2nd, then the 2-3 and 3-4 very close.
According to the book, RGM"s "1.8:1" is without kickstart facility.

With kickstart, he offers "2.05:1"
Thanks for the replies, I think I'll get the close ratio one as I am not a great fan of "short" first gears. I have found very little in my gearbox that can be re-used, luckily the bearings were tight in the shell and required a fair bit of heat and persuasion to remove, so I think I'll put together the RGM C/R gears on Andover Norton Shafts, with the layshaft bearing from Mick Hemmings in my existing shell.

I have no personal knowledge as to whether all gear pairs may be interchanged in the same case etc.

However: there are far more choices than what is offered; for example, the std. 14/28 1st gear pair when used in the "close ratio" box gives:
with the same RPM changes on the 2-3 and 3-4 as the full close ratio.

The Daytona 1st gear, when used with some std. parts including the high gear pair:

Why doesn't RGM etc. offer other ratio choices?
1. they may not have all the parts
2. higher profit margin on gears they make
3. it will just precipitate the following questions:
"which ratio is best for my bike", for which a definitive answer is not possible.
Hey Graeme...Baldrick from Mount Maunganui in NZ.

Go for the RGM close ratio.
I have done 4,000 miles on RGM CR gearbox on my 850.
It is amazing with the tall first gear good for getting in and out of roundabouts.
As the bike is a MK1 it also removes that large gap between 2-3rd.

I do alot of long distance riding with the wife...That's 24 stone without baggage!
We can cruise up most big hills without the need to change down.

I have also added an RGM belt drive and it is now as smooth as a Japa and I can park it on my mums concrete as it is now as oil tight as a fishes bottom!

Thanks for the input Baldrick, mine is a 750 so it doesn't have the low end grunt that yours probably does, and what I'm currently thinking is Daytona 1st, with RGM C/R 2nd , 3rd, & 4th. Anyway I have to save my pennies for a bit before I order the parts, so still got time to change my mind a couple of times yet.

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