13-42T Final Drive on an SF?
#1
13-42T Final Drive on an SF?
I ride an SF ~1/3 off-road, ~1/3 gravel roads, and ~1/3 pavement. I realize the SF isn’t the best suited for off-road use but I have 50/50 DS tires on it and that’s how I ride it regardless.
Stock final drive on an SF is 14-39T. I am currently running 13-39T and I am very pleased with the overall results that reduction has given me in all types of riding. However, I was in some particularly gnarly & steep off-road terrain the other day and I found myself continually hunting for another lower gear. It got me thinking about trying a 13-42T combo.
I calculate that it would cause me to spin an extra 700-800 rpm in top gear at 100kmh (60 mph), and I hope it would give me better engine braking on steep 1st gear descents, and a little extra rear-wheel grunt on steep ascents and in mud.
A quick search for others running a 13-42T final drive on an SF came up inconclusive, but I’d still like to hear recommendations from anyone who’s tried it.
Stock final drive on an SF is 14-39T. I am currently running 13-39T and I am very pleased with the overall results that reduction has given me in all types of riding. However, I was in some particularly gnarly & steep off-road terrain the other day and I found myself continually hunting for another lower gear. It got me thinking about trying a 13-42T combo.
I calculate that it would cause me to spin an extra 700-800 rpm in top gear at 100kmh (60 mph), and I hope it would give me better engine braking on steep 1st gear descents, and a little extra rear-wheel grunt on steep ascents and in mud.
A quick search for others running a 13-42T final drive on an SF came up inconclusive, but I’d still like to hear recommendations from anyone who’s tried it.
#3
I am quite sure that an extra 3 teeth on the rear sprocket isn’t going to unleash some kind of secret off-road beast lurking within the SF. I am at a crossroads of considering a 351S, DR400, or something bigger like a DR650 or XR650. I’d really like to keep the weight & size down so something like a KLR is a non-starter.
#5
The final drive of the S and SF gear ratios are the same, the SF uses a 39 rear cog to compensate for the smaller rear wheel.
#7
Just makin sure, some people think that by going to sf wheels and sf gearing they get better final drive ratio .
#9
Keep us posted with your review on the 15/40 combo.
#10
I hadn't even realized that there is a 40T available for the KLX, but I can see that pairing nicely with a 13T. I look forward to hearing how it works out.