Header pipes not warm at same time

Hey all, I just went out with my cousin to look at another '85 Maxim X, and this one was quite rough, but I told him that if it fired up right away without issues, it might be worth the asking price. Mine looks like the bargain of the century compared to this one, BTW.

It turned over quite a bit, before eventually starting. It sounded like it just ran on two cylinders, and checking the header pipes confirmed this. The two inner ones were cold, while the outer ones were warming up. It seemed to fire on all four eventually when a large amount of throttle was applied, but it never did get to run properly.

The owner claims it just needs the carbs cleaned. Would gummed up carbs do this (pilots clogged, maybe?), or could this be an electrical problem of some sort?

 

If it ran on all four with the throttle full open then it's carbs. No matter what you'll need to catch up an all of the undone maintenance. Old bikes are not ever going to be a matter of just cleaning the carbs for them to be safe and reliable.

 

^ what he said ^ the bike runs mostly on the pilot jets untill about 2k rpm

good read on basics of the jets
TALKIN' TECH: Various thoughts on various issues

 

We drove the three hours back home, bikeless. It was just too rough, and he wouldn't budge on price ("I spent $350 three years ago getting the carbs cleaned and all tuned up").

 

Send him a postcard with your phone number and bottom-Loonie offer. You might get a call in a few weeks.

 

Maxim-X ? What motor is that ? Looks water-cooled.. was it used eleswhere ? Just curious..

J

 

It's an XJ750X, in Canada at least. I think it's a 700cc elsewhere. Made in '85-'86, had a 5 valve per cylinder top end, very similar to the FZ750. Printed materials at the time had it at 90 crankshaft HP. They ran sub 11.7 in the quarter mile. Very fast cruiser, even thirty years later. Will pull past the 10000rpm redline, in top gear--130mph.

Few people today know what they're about.

 

The X was 750cc everywhere but the U.S. due to the shortly-lived import tariff on motorcycles over 700cc.

The main differences between the Maxim-X engine and the FZ750 are the bottom end (so the engine can fit into a cruiser frame), and the cams (midrange power and low torque on the X). Otherwise it's the same Genesis engine.

 

Aha - thanks. I have an FZ750 myself (nothing special but it runs nicely and doesn't look too shabby from 10 yards) but I didn't recognise the bottom end.

Cheers
J

 

I read that the bottom end is from the XJ900.

 

The cams are different? Would swapping out for FZ cams make a power difference, or just move it around?

 

Never mind, looking at the fiche, the part numbers are the same for the FZ750 and the Maxim. The Fazer ones, however have a different P/N.

 

You're right. Brain fart on my part.

 

AFIK that is correct.