n00b question about revs

[ForresterQ]

Hi All,

I have an 06 GPX and wonder what revs it should be doing when cruising at a speed of 70 or 80.

My instructors bike is a scorpio 225 and the tacho is fogged over so I can't use that as a reference.

Since most of my experience is in cars I'm still learning to listen to the bike, I have a feeling the gears I use are too high and it's revving too low.

What's the go?

[Desmo]

Whatever revs it's doing in fourth or fifth.
Not screaming, not labouring.

[kritas]

Can you suggest using "Brasso" on your instructors tacho???

You can buy it from Coles, it's like $7-$9 a bottle.... Works an absolute treat! Gets rid of any murky/sandpapered effect on plastics and perspex, as well as metals...

Also, what Desmo said =)

[Gixxerguy]

It was probably fogged intentionally, a lot of motorcycle instructors disconnect their tacho's or obscure them in other ways to stop the students watching them and being distracted by them.

[Frogger]

RPM guidelines
The EX250 engine, along with those on most 'sporty' bikes, was designed for high-rpm use. There seem to be some compromises which make it harder to use at engine speeds lower than about 6000 rpm. Basically, there's no reason to ride any lower than 5000 rpm, except for while sitting at a light. Even then, you can't depend upon the engine for any power that far down.

The following suggestions are just that. Get used to what works for you, and keep in mind that your Ninja likes to work at high engine speeds. These are not guidelines for how to get the best gas mileage from your engine. However, they will help you avoid stumbling at low rpm and keep the engine spinning fast enough to be of some use if you need to suddenly go faster.

Mellow takeoff from a light: 3-4000 RPM
Aggressive take-off from a light: 5-6000, and only use small throttle openings below 5000 (less than 1/3 throttle).
Never cruise below 6000 rpm
Never ride in-city at lower than 7000; this gives you more available power if you need to move
In spirited riding (twisties) never drop below 8000
On the track, 9000 is about the lower limit, usually aiming for 9-11,000

this is from this site Accelerating, changing gears - Ninja250Wiki its got good info i suggest book marking it.

[darkfibre]

While you are learning, ignore the tacho. Try different gears at the same speed and find your happy place. Once you have got cruising about at a steady speed sussed, then its tacho time. Thats when you find the best point to change gear and stay in the engines best power range.

[thro]

the "sweet spot" for cruising around on a kwakka 250 is around about 7-8k.

whatever gear you need to be in for that speed in that rpm range is fine.