Poor fuel economy

Message

beerbaron · #1 Unread post by **beerbaron** » Sun Sep 11, 2005 6:31 am

Hi there, it seems to me that my motorcycle has a poor fuel economy compared with Toyuzu's motorcycle. I have an FZ600 and he has an XJ600, they both have the same engine but with different carbs. His is 70 Hp and mine is 55 Hp.

Bue the problem is that he gets something around 50 MPG when I only get 35 MPG. My carbs are correctly balanced (spark plug seem fine). I talked with him about his riding style and it seems his is more aggressive then mine. He rides around 7000 RPM when I ride around 4500 RPM.

I was wondering what could cause such a big difference in gas mileage? 35 MPG doesn't seem good at all if I compare with other motorcycle.

BeerBaron

ZooTech · #2 Unread post by **ZooTech** » Sun Sep 11, 2005 7:50 am

Weight difference? Altitude difference? Engine mods? Is it hilly where you live and flat where he lives?

beerbaron · #3 Unread post by **beerbaron** » Sun Sep 11, 2005 2:40 pm

I weight 120 pounds, no mods original jet size uless someone before me drilled em, it's fairly flat in here.

txbadboy · #4 Unread post by **txbadboy** » Tue Sep 13, 2005 9:29 am

wrong octane? with a sport bike, i would imagine you would need to use at LEAST midgrade, if not premium, if you arent already. dirty carbs, some sort of blockage? carbs are balanced, but are you running rich by chance? have you tested your coil to see if youre getting insufficient spark? are the plugs gapped correctly? clean air filter? hmmmm....thats all that comes to mind at the moment. good luck!

beerbaron · Tue Sep 13, 2005 12:02 pm

It seems your right spark plug 1 & 2 are carbonised. I'd be surprised if it were a dirty carb because I opened em in june and they were clean. I'm starting to think that maybee I didn't balance carbs 1&2 as well as I tought. Unless you have another idea ?

BeerBaron

txbadboy · #6 Unread post by **txbadboy** » Wed Sep 14, 2005 8:55 am

well, ive never dealt with a 4 cylinder bike before, ive only had a single and am now on my 2 cylinder, so im not quite sure how that would work with the 4....however, its clear its running rich on that bank. my first bit of advice, if it were me, would be to make sure theyre balanced correctly. might be well worth the investment to purchase a set of carburetor synchronizers for a more accurate tuning. you might also look into making sure all the idle mixture screws are set properly, as thats probably closer to the area of your problem. again, ive never dealt with the 4's, so if im mistaken, someone correct this..im just going with logical steps. also, are you smoking from the pipe at all? good luck