6TH Gear Problem
Discussion
I was on the home tonight sat on the motorway in 6th @ 70mph(honest?) and had to twist the throttle to the stop in order to stop the usual blind car driver from putting me in the barrier, the bike felt like it was running out of juice for a second or so the picked up as usual.
After showing the driver the error of his ways via hand signals I tried it again and the same happened? It doesn't do it in any other gear apart from 6th?
Its a 1998 ZX6R please help!
After showing the driver the error of his ways via hand signals I tried it again and the same happened? It doesn't do it in any other gear apart from 6th?
Its a 1998 ZX6R please help!
It's very likely gear ratio problem. For daily use bikes optimum acceleration can be reached up to the 4th gear, the higher gears are relatively to smooth the engine and increase fuel economy, while practically without significant acceleration.
Ask mechanic to modify the gear ratio than standard when bike manufactured to gain more acceleration of high gears.
Ask mechanic to modify the gear ratio than standard when bike manufactured to gain more acceleration of high gears.
It's a 'characteristic' of highly-tuned small engines. They need to be revved hard to produce any meaningful power. If you want an engine which will pull hard from 70 in 6th gear, you probably need a twin rather than a four.
An improvement can be made by putting a one-tooth smaller sprocket on the gearbox. This will have the effect of making the bike rev harder for any given road speed and improve pickup. It will, however, reduce your top speed as the engine will run out of revs earlier.
An improvement can be made by putting a one-tooth smaller sprocket on the gearbox. This will have the effect of making the bike rev harder for any given road speed and improve pickup. It will, however, reduce your top speed as the engine will run out of revs earlier.
littleredrooster said:
It's a 'characteristic' of highly-tuned small engines. They need to be revved hard to produce any meaningful power. If you want an engine which will pull hard from 70 in 6th gear, you probably need a twin rather than a four.
An improvement can be made by putting a one-tooth smaller sprocket on the gearbox. This will have the effect of making the bike rev harder for any given road speed and improve pickup. It will, however, reduce your top speed as the engine will run out of revs earlier.
what he said^^^An improvement can be made by putting a one-tooth smaller sprocket on the gearbox. This will have the effect of making the bike rev harder for any given road speed and improve pickup. It will, however, reduce your top speed as the engine will run out of revs earlier.
lenientism said:
It's very likely gear ratio problem. For daily use bikes optimum acceleration can be reached up to the 4th gear, the higher gears are relatively to smooth the engine and increase fuel economy, while practically without significant acceleration.
Ask mechanic to modify the gear ratio than standard when bike manufactured to gain more acceleration of high gears.
Are you posting through babelfish?!Ask mechanic to modify the gear ratio than standard when bike manufactured to gain more acceleration of high gears.
PolarExpress said:
Dropping a tooth on the front sometimes doesn't lose you vmax - you can jsut get there quicker. IINM, a lot of newer bikes have 6th as an overdrive for fuel economy, and vmax can be reached in 5th on the standard sprockets.
Fuel economy would be the thing to consider if changing the gearing on the bike. A one tooth reduction in the front sprocket would likely have about a 5% to 8% reduction in gearing and may also have about a 5% reduction in fuel economy. Your speedo will also over read by an additional 5 % to 8% which will make it look as though you are going faster than you actually are.A simpler solution is simply to drop to 5th when you want to accelerate away!
black-k1 said:
Fuel economy would be the thing to consider if changing the gearing on the bike. A one tooth reduction in the front sprocket would likely have about a 5% to 8% reduction in gearing and may also have about a 5% reduction in fuel economy. Your speedo will also over read by an additional 5 % to 8% which will make it look as though you are going faster than you actually are.
i went up a tooth at the front on my old RF600, it gained me 5mpg. i'd expect a similar loss by going down at the front.as to the speedo, depends on the bike. if it reads off the gearbox then yes it'll be out. if its the older style with a cable to the front wheel it wont be affected.
MaximumJed said:
I take it I am one of the only people who read the OP as the bike hesitating when he wound the throttle open, not just a not enough acceleration thing? My old 540 used to do the same if you suddenly depressed the throttle, almost like it was drawing breath.
low revs & high throttle = low airspeed in the intake tract, that can cause hesitation due to the fuel not atomising properly. could even be the accelerator pump (if its got them) pumping too much & basicly flooding it.MaximumJed said:
I take it I am one of the only people who read the OP as the bike hesitating when he wound the throttle open, not just a not enough acceleration thing? My old 540 used to do the same if you suddenly depressed the throttle, almost like it was drawing breath.
My old Thunderace was prone to this. Exactly the same symptoms. Carb icing?Hooli said:
MaximumJed said:
I take it I am one of the only people who read the OP as the bike hesitating when he wound the throttle open, not just a not enough acceleration thing? My old 540 used to do the same if you suddenly depressed the throttle, almost like it was drawing breath.
low revs & high throttle = low airspeed in the intake tract, that can cause hesitation due to the fuel not atomising properly. could even be the accelerator pump (if its got them) pumping too much & basicly flooding it.Review of the 2000 ZX6R said:
The engine responds very crisply to throttle input and the four 36mm Mikuni carburettors are almost too sensitive to the quarter-turn throttle. In top gear there's a slight hesitation at around 8,000 rpm, which corresponds to just under 160km/h - the Kawa takes a few nervous seconds to pull through it, but at ten it comes back on song and lights up like a skyrocket, all the way to the redline at 14000. I can't prove it, but I think the carburetion is momentarily rich until the Ram Air effect comes into play, pushing a whole lot of extra air into the equation.
so it might be a characteristic of the bike?black-k1 said:
PolarExpress said:
Dropping a tooth on the front sometimes doesn't lose you vmax - you can jsut get there quicker. IINM, a lot of newer bikes have 6th as an overdrive for fuel economy, and vmax can be reached in 5th on the standard sprockets.
Fuel economy would be the thing to consider if changing the gearing on the bike. A one tooth reduction in the front sprocket would likely have about a 5% to 8% reduction in gearing and may also have about a 5% reduction in fuel economy. Your speedo will also over read by an additional 5 % to 8% which will make it look as though you are going faster than you actually are.A simpler solution is simply to drop to 5th when you want to accelerate away!
Speedohealer cured the speedo over read.
wingnut. said:
Thanks guys, it does sound more of a trait rather than a problem, I've just remembered its 2 teeth bigger on the rear sprocket, not sure how much of a difference that would make though?
as a rough rule, 3 teeth on the rear is worth 1 tooth off the front. so its already geared down for acceleration.littleredrooster said:
It's a 'characteristic' of highly-tuned small engines. They need to be revved hard to produce any meaningful power. If you want an engine which will pull hard from 70 in 6th gear, you probably need a twin rather than a four.
An improvement can be made by putting a one-tooth smaller sprocket on the gearbox. This will have the effect of making the bike rev harder for any given road speed and improve pickup. It will, however, reduce your top speed as the engine will run out of revs earlier.
the man speaks sense An improvement can be made by putting a one-tooth smaller sprocket on the gearbox. This will have the effect of making the bike rev harder for any given road speed and improve pickup. It will, however, reduce your top speed as the engine will run out of revs earlier.
RSV-R anyone?
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