Gearing up on top gear

H

Harvey

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Joined
Jan 25, 2004
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327
Location
upstate NY
Any one ever try gearing up 1 tooth on an SRX,specifically a 2002 700?I have dropped 1,2 teeth but never tried going up one.Thought maybe one of you guys have.thanks-Harvey
 

If your referring to stock gearing, Yamaha tends to run the gearing a little taller than the machine will ever reach to temper the wear on the belt a little. Don't thing going any taller will help you, dropping down a tooth however will provide you with a little more low end grunt.
 
Ya I have geared down a couple different ways and am now back to stock gearing,the sled pulls hard out of the hole,thought I would try going up 1,seems the clutch would be more efficiant if It reached higher speeds earlier in the clutch shifting out-thanks-Harvey
 
I am running 23\40 gearing in my 2002 srx. I did this on the advice of an experienced srx tuner. Does run well. Have never run it with the stock gearing but am curious as to how much difference there is. Thinking about trying 23\39 this year. Iwas told with the stock gearing 800 twins would get too far out ahead for me to catch them. Is this true? I don't have any problem with them with 23\40 for sure. Kinda wonder though if I am spinning more by being geared down and losing acceleration versus stock gearing. I am just an aggressive trail rider who likes to pinch it off with the boys on the lake. Only running 144 1.075 studs in a 1" camo finger track. Wuold like to hear from guys about the differences in gearing. I can see 120 on speedo on ice how much more would I see with stock gearing. Any difference in gas mileage? I am always interested in reading posts on gearing for srx's let's hear from some of you well experienced srx guys Please!
 
I would like to hear some more too,I was geared down 1 on top,tried 2 on top,and now am back to stock.My sled pulls like a horse,kind of flattens out at 100 or so on the speedo then slowly pulls up to around 113 on gps.I have not tried it on a long ice stretch,only on hard pack.I am running a team secondary with heavy hitters in the primary.I installed 8 inch rear wheels and oversized idlers in the 6 idler positions,man track spins real free now.I really had hoped someone tried gearing up a little and tuned there clutch for it and had some good results.I should just leave it alone and ride it but its fun wrenching on it,especialy when you feel a difference.These sleds should see close to 120 on the gun shouldnt they?
 
There is nothing wrong with gearing up as long as you have enuff motor to pull it, if you gear the sled up alot and dont have the power to pull it, its gonna go SLOWER, as the motor does not apply enuff torq. to the sec. clutch and its gonna begin to backshift to a more reasonable ratio to keep gripping the belt, and with taller gearing this means your gonna be in a lower gear ratio in the primary clutch portion.( your belt will be way low in the primary). If you want flat out wide open top speed, then stock gearing 23/38, will get you 120+ mph, but sometimes you can achieve the same top speed with 22/38 or something close, as the clutch is more efficient and shifts out further from the meat of the torq. curve from the engine, you just have to try it and see what your sled likes. Its also gonna have a effect on the clutching in the sled, its easier for a sled to pull heavy weights with steeper gearing, and vice versa. You have to ask yourself, "what kind of riding am I doing 90 percent of the time"?????? then set the sled up for that , not the other 10 percent!
 
Harvey, when you ran 113 on gps what did your speedo say just curious. Also it seems these srx's should run close to 120 gps with the stock gearing. where did you get your 8" idlers? Sounds like these might be worth while. Also what have you run against for other sleds and how did you do?
 
The yamahas we checked-SRX 700,SX 500,SX700 all seemed to be around 7 mph off,the viper on the other hand was close to 14 mph off.Polaris 700 was close to accurate,and an MXZ 600 was right on the money.Biggest sled I have ran against was a new ZR 900 last year with the diamond drive,he only pulled 99 on gps,but man it had wicked mid range,if they ever make gears for the diamond drive that thing will fly.I dont really run in any local drags,pretty much just play around with the guys I ride with.I think the big wheels will help a lot,I could tell how much easier it rolls just by taking it out of the garage today.I know I have more than 113 mph in this sled,just need to get my clutching dialed in.I had the needle way down past 120 the first year I had it,did not have the gps yet but am sure it was far enough past to be around 120.That was with a heavy hitter setup.Now I need to dial in the team secondary.It pulls like a horse to about 100-105 then slowly climbs up to 120 on speedo. As far as the big wheels go I bought the offset axle kit from performance engineering and machine along with the 8 inch billet wheels,you could just go for 8 inch rubber/plastic wheels-alot cheaper.I was foolish to spend the money on the billets,but they look cool-lol.Also,the other 6 idlers are skidoo 5.350 idler wheels with a 25mm/1" bearing-Harvey
 
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I've got a question that goes along with this thread some of you senior members can probably help me with. I'm trying to dial in an 02 Viper with the Fixx King Cobra kit and a 136" M-10 with 8" rear idler wheels. Yesterday I tried gearing up instead of down and the primary wouldn't fully shift out so today I'm trying gearing down. I decided to drop down a tooth on the top gear and go up one on the bottom so I'm at 21/39 1.83 ratio. I'm also running a 1.25 Ripsaw track 136". I figure the taller lug has got to affect final drive ratio as well as the length. Does anyone know the mathmatical formula for calculating the final drive ratio? Oh yeah running heavy hitters and the stock helix with a spring marked silver from Jeff Simons piped Viper clutch setup.
 
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Rider weight has a lot to do with gearing a sled. Lighter riders benifit from stock or gearing up where as heavier rider need to gear down.
 
I was running 22/37 gears and chain from a 700 SX. I also loaded the weights with the heaviest rivets I could get along with a 51/37 helix. Also running oversized idlers and 94 VMax sliders (lower profile). The only problem is I am running a stock track and no studs so my track did nothing but spin. A friend was running this set up here and there was nothing that could touch him (drag and top end). Apparently he got 125 on the gun on ice. I switched back to stock because of my traction issue. My track spins still but not as crazy.
 
Harvey said:
I would like to hear some more too,I was geared down 1 on top,tried 2 on top,and now am back to stock.My sled pulls like a horse,kind of flattens out at 100 or so on the speedo then slowly pulls up to around 113 on gps.I have not tried it on a long ice stretch,only on hard pack.I am running a team secondary with heavy hitters in the primary.I installed 8 inch rear wheels and oversized idlers in the 6 idler positions,man track spins real free now.I really had hoped someone tried gearing up a little and tuned there clutch for it and had some good results.I should just leave it alone and ride it but its fun wrenching on it,especialy when you feel a difference.These sleds should see close to 120 on the gun shouldnt they?
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......Hey harvey, my o2 srx also ran 113mph on a radar gun up on the lake...We were running along a stretch just as you come out of stump alley towards sport island pub....It was like a mile or so long, It was like 40 degees that day and I also weigh 230lbs...My buddies rx1 ran 115mph, a stock zr900 ran 116mph and worked tcat ran 123mph
 
well i don't know but with the stock gearing my 01 srx ran 115 in 2000 feet on the gun it was the first week of April 2004 and +6 degrees celcius and i weigh 220 pounds it's clutch and bender can and reeds other then that it's STOCK
 
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