new member, 650 maxim questions

hey everyone, i just joined the site today. Lots of good info and pics!
This site has inspired me to keep my bike and improve it. I have been contemplating getting a new bike, and still may, but i feel there is hope for my 82.

I just have a couple of general questions mainly regarding performance. In the three years I have owned it doesn't seem like it has much power, and i assumed it was because it is an older bike. But my one friend was actually a previous owner of it and he says it feels like it has lost alot of power since he had it. And it only gets about 35 mpg when i have checked it. how well are these babies supposed to do on fuel usage?

so first, how much power should it have? i know its heavy, but the front wheel barely pulls up in high revs. my friend has an '03 klr650 single cylinder and he blows me away. my bike has 4-1 exhaust, and i guess that is aftermarket? but i don't know who makes it, and i think it is old. also my friend said he used to run aircraft fuel in my bike. Does burning very high octane mess with the rings or valves?

So i'm guessing checking valve clearance, cleaning/synchronizing the carbs would do a world of wonders? what is compression supposed to be? maybe new piston rings.

Lastly, how much would mods help such as open air filters, jetting the carbs, milling the head?

Any help would be appreciated and would help me help a neglected old bike

 

Hello,and welcome to the site! Your bike,by virtue of design,has a different power band than a "thumper". It is like comparing apples and oranges. The KLR has gobs of low-end torque,but I believe your bike would have better top end perforfomance.The XJ is fine bike it its own right,but it was designed more as cruiser than an outright performance bike.If you want to do wheelies,you may wish to get a newer,more powerful scooter.A carb cleaning/synch may help your fuel mileage,but be advised that abrubt and frequent throttle openings can severely diminish the MPG that you experience.If I ride my bike aggressively,I get about 33 mpg. If I ride it easy,and take it for a longer ride,I get about 52 MPG. When you start modifying the bike,you open up the dependability and tuning can of worms. I am not trying to discourage you,but these bikes are generally as reliable as a hammer in stock form. Although they can be hard to dial-in,some people love pod filters. Others think they are the DEVIL! Perhaps someone else can impart some wisdom regarding the mods that you have discussed. Best of luck to you with your bike!

 

I get between 45-50 mpg on mine. It's got all the power I need. The powerband on these really starts in around 6000 rpm up to redline. You can do 65 in 5th gear, drop to 4th to pass, and drop to 3rd if the guy decides to clown around. Blow by him, back into 5th and you probably be hanging on tight at 90 wondering how you got there! If you're getting such low mileage, either your horsing the daylights out of it, or you need some carb adjustments, hopefully not internal work.

Check out my new pic in my gallery. I just finished restoring a Vetter Windjammer IV fairing. Yesterday was the first day out with it.....all the difference in the world.


dave

 

Funny you mention a friend with a klr 650. I have a friend with an '04 klr 650 that I raced on my '80 650 maxim. His bike lifts the front end off the line..mine doesn't. I still beat him though. Stayed out in front of him the whole way actually, and pulled away pretty quick at the top end. That was with some seriously jacked up carbs at the time too.