Starting issues.

I have a 1981 maxim xj650 that ran all last year. Now it won't start. I had the carbs cleaned / rebuilt. Battery was on a battery tender. It's sparking the engine just won't turn over. Have no mods done just routine maintenance done. Just bought 4 new spark plugs and gapped properly. Still not catching.

 

Fresh Gas?
Fuel flowing from "PRI" setting on petcock?

Set on PRI, count to 30 , full choke, and hit start, what happens?

 

How many miles on the bike?

What "routine maintenance" has been done?

"Had the carbs cleaned/rebuilt" sounds like maybe you didn't do the work. Has it run since then?

Are your valve clearances in spec?

 

Skip: Fuel flows great when on prime. Not fresh gas though

Fitz: yes someone cleaned them and rebuilt them for me. The bike ran until it sat for winter. Then didn't start so I had the carbs cleaned and rebuilt. Still doesn't run. The routine maintenance was new tires, brakes and lines, and battery, and spark plugs, I have not done a valve clearance check. I'm looking on how to do that now. I bench synced carbs myself before putting them back on. I'm bout to take them off and check float levels. Ooo and there's 26k miles on the bike.

The bike just won't turn over. Idk if it's a coil, or gas problem. I hear it trying but just won't budge. Before I had the carbs cleaned it sounded like possibly flooded. But now it just won't roll over.

 

It needs new gas if you didn't stabilize it before storage.

That's a dead battery. If you hit the button, and it doesn't do anything, you need to charge the battery(and make sure it's topped up correctly).

If you're doing this a lot, and you leave it stored over winter, it's a good idea to at least invest in a trickle charger.

 

"Won't turn over" means no spinning at all.

Is it actually not turning over; or is it spinning itself silly and not FIRING?

People are giving you suggestions related to actually not turning over, when I suspect your issue is that it turns over but won't FIRE UP.

CHECK YOUR VALVE CLEARANCES. At 26K if they were ignored, you could very well be at the point where it quits running because of it.

 

Back to basics!. Does "Sparking the engine" mean you have spark at the plugs and are the plugs wet?

 

Sorry yes the starter is just spinning but it won't fire. New to working on bikes so I don't know too much including terms.

 

Hmm I'd say get new spark plugs just to be sure and check all wires for a good solid connection. You can test your ignition system with a ohm meter to check for proper voltages as well. Check to make sure your actually getting fuel when from the petcock turn it to prime and see if fuel flows out the hose. Check for a cloggedmfuel filter as well possibly. You need three things to start an engine spark, fuel, compression. Check off each you have. If all else fails and it just won't crank after checking all these components as a last resort to try, grab a can of starting fluid, open the air box under seat and with the precision spray extension spray a liberal amount for a couple second into the air box then try to crank the bike with full choke.

 

Yeah, replace the fuel. If that doesn't work, try using starting fluid. If that works then you have something wrong with your carbs. If not, trying something else

 

New gas. Same result. Not firing just spinning. It kinda sounds like it might be flooded.

 

If you did flood it, you may have killed the plugs. Spark plugs can become saturated with gas and they stop firing. There's no way to effectively "fix" them. Install a brand new set of properly-gapped plugs.

Seriously. If ignored, the valve clearances just get tighter and tighter until one day the motor simply won't run anymore. Check your valve clearances. CHECK. If you find they're all horribly tight, then you know where to start. If they're fine, then do a compression test and let's move on.

Valve clearance how-to: http://xjbikes.com/Forums/viewtopic/t=14827.html
Part Deux: http://xjbikes.com/Forums/viewtopic/t=29209.html

You may also need to revisit the carbs. Unless the shop was truly knowledgeable (rare) then your idea to WET-check the float levels is a good step.

But again, the valves have to be in spec before you can hope to get the carbs properly adjusted.

 

Ok. The valves were in spec according to Haynes manual specs. After checking I decided to try and start again. And boom started. But it was reving super high. Not idling it would just shoot to 7k RPMs and go higher. After fiddling with throttle cable it would idle around 3k rpm. I turned the bike off now I'm not getting any power at all. No lights no nothing.

 

Ok figured the problem out. Had a loose metal prong on the fuse box. So it's starting. As it starts though it shoots to an extremely high rpm. So I shut it down. I tinkered with the throttle around the carbs and it lowers it. But as soon as i give it has it goes up REALLY high and never comes down. Is this a result of the cable being bad. Or the thing on the carb not coming all the way back down.

 

did you try adjusting the cable where it goes into the handlebar grip it might not have enough play in the cable if any

 

Ruh-roh. Haynes has it wrong. Intake spec is .11mm ~.15mm. Haynes picked up a mistake (typo) that Yamaha made and it went downhill from there.

If you used the Haynes your intake valves may or may not be truly in spec. Re-check.

 

Will check again then. I book marked the page u earlier told me about so should I go by those numbers??? And also i think I might need to redo the carbs. Bc I realized if I left it on prime it would shoot up to high rpms. But after I turned off the gas to on it would still be high but settle down then eventually die. So I feel like it's something with the carbs and gas flow.

 

Even though it took me most of my summer. I finally got the bike running amazing. I ended up taking to a shop and the guy was impressed with how my carbs were and the condition the bike was in. It ended up costing me i just under $500 but that was because i needed new carb intake boots. which he said was y my bike wasn't doing so good bc i had a leak in them. So i spent almost 400 right there and then he synced the carbs up correctly. Now my bike is a freaking BEAST. Running like a champ. Now i can start with cosmetic stuff, like new paint, and kinda modernize it but still stay close to stock. Thank you guys for the help with carbs and valves

 

Congrats LilBig - - Catch-up on your riding while it's still warm, clean 'er up in the winter.

Has anyone bothered to send "Haynes" a note on this typo?? I mean it's been 35 YEARS !! A little correction slip glued to the back cover would do.

 

I am having the same problem, dont know what it is.