Ninja 250 MPG

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Jas0n · #1 Unread post by **Jas0n** » Fri Aug 17, 2007 8:11 pm

I'm really not sure how an engine works, so help me out here.

When I first started biking, I was always blasting the throttle at 7+ rpm to accelerate. Now, I've become much more conservative of gas (I dont know why) and I'm thinking that 7+ rpm isnt really helping.

So on my way back home from the skatepark, I kept the bike in 6th gear almost 80% of the time. The bike was running at 6 or below the whole way home, and I felt my efforts weren't working.

When I'm going up a hill, I have to use extra throttole in 6th gear in order to get some accerlation. However, if I had just kicked the gears down to about 4th or 5th then I would barely need to use the throttle but be reving it at 8+ rpm.

So anyways... my question is.. Does using 30% throttle in 6th gear, but reving at 6 rpm save more gas than using 20% throttle in 5th gear but reving at 8+ rpm?

Flesher · #2 Unread post by **Flesher** » Sun Aug 19, 2007 12:11 pm

You may save some gas by running in a higher gear and therefore lower RPMs. However consider this;

Most motorcycle engines are made to run in the upper 1/3 of their RPM range, and it is in this range that the least wear and good power is made. When you lug an engine, as you were doing, you are damaging your engine, the oil pressure is too low under that load to provide adequate lubrication. Spending money to fix an engine seems a very poor compormise to save gas IMO.

Scott58 · #3 Unread post by **Scott58** » Mon Aug 20, 2007 6:27 pm

Stay in the proper gear for the situation. You may want to consider dropping a tooth or 2 in the rear sprocket, but don't go to crazy with that either.

Jas0n · #4 Unread post by **Jas0n** » Wed Sep 05, 2007 2:47 pm

Alright, I'll keep it in the necessary gear. However, holding the clutch in whiel going down hill doesnt hurt right?

Shorts · #5 Unread post by **Shorts** » Wed Sep 05, 2007 3:17 pm

Jas0n wrote:Alright, I'll keep it in the necessary gear. However, holding the clutch in whiel going down hill doesnt hurt right?

Why would you hold the clutch in when rolling downhill? Are you coming to a stop at the bottom of the hill? Are you down shifting while going downhill?

Jas0n · #6 Unread post by **Jas0n** » Wed Sep 05, 2007 3:24 pm

My neighborhood is really hilly. At the bottom is my house, and I try to make as little noise as possible. Holding the clutch in pretty much puts my engine in idle mode and even the people in my house don't notice I pulled in. Its bad I suppose?

Shorts · #7 Unread post by **Shorts** » Wed Sep 05, 2007 3:31 pm

Jas0n wrote:My neighborhood is really hilly. At the bottom is my house, and I try to make as little noise as possible. Holding the clutch in pretty much puts my engine in idle mode and even the people in my house don't notice I pulled in. Its bad I suppose?

Well, since it removes the power from the bike, it takes away alot of control you'd have to evade in a quick situation, at least my preference in riding down the hill. But I understand you're wanting to keep the bike quiet downhill, engine braking can be pretty loud, I know my bike is gruffy in those situations. I think I'd try slowing further down with your brakes to take some work off the engine, maybe a higher gear to still get engine braking with less noise. Again, just what I'd try, I don't know your road. And I have held in the clutch to pull into parking lots off the road and such while holding in the clutch - to coast in basically. So I can see that - but not a long ways

Veda · #8 Unread post by **Veda** » Thu Sep 06, 2007 12:22 am

Can the people in your house hear your bike when it is in gear? I know it sounds loud to you, sitting on top of it and all, but I would be surprised if it was loud enough to annoy people inside their houses.

JBA111 · #9 Unread post by **JBA111** » Wed Oct 10, 2007 6:17 pm

To get the best gas mileage use the gear stated for your speed at the RPMs suggested by the MFG.
You;ll get the best mileage by learning how to roll on the throttle smoothly and some slower. and quit bliping the throttle. Even downshifting can be done smooth and precise without bliping the throttle. You will have to increase the revs but get the hang of doing this just to mesh the gears at the right speed and right RPMs. it takes practice but is really cool when you get it down pat and you will get some of your best MPG.
but be smooth. Back durring the 70s and the oil embargo they was a saying about stepping on the gas pedal like their was an egg on it. So you learned to gently and slowly press the pedal. you can get the same ideal with the hand throttle. It works.

Brackstone · Thu Oct 11, 2007 6:03 am

I followed the specifications of what was in my manual and tried to keep it under 4k RPMs for the first 400 miles.

For the 400 miles I had I only needed to fill up once. If you keep the RPM's within manufacturers spec I think you can probably go at least 250 miles if not more without filling up.