Starts in neutral dies in gear

hey guy's my 83 xj750 starts and idles fine in neutral. but when I put it in gear it dies. this only happens when the bike is warm and not hot. it also seams like if I rock the bike in gear the problem goes away. :roll:

 

It very well could be your neutral safety switch. I had mine go bad with exactly the same symptoms. I am not sure if the part is available anymore, so I just bypasses the switch and my problem went away. I am sure if you search neutral switch you will find alot more information on it and can make you own decision.

 

yea the safety switch was my first thought as well. the question I have for you is if you try to start in gear (with out depressing thew clutch) does the bike leap forward?

 

It would leap forward if the safety devises would let it start, which they don't.

If the clutch is pulled, and the engine running in gear, it doesn't leap forward, but it could drag forward if the clutch isn't adjusted just right.

 

Mine did that when the kickstand safety switch was out of whack.

 

i removed my kickstand switch. no worries!

 

well I check out the different switches and safety devices, all seems in order.

no the problem I am having is that I can not get it to reproduce the symptoms. it seems to have fixed it's self ( I find this very scary ). anyway when I figure out what was / is happening I'll let you guys know :roll:

 

disconnect the side stand safety switch in the headlight bucket and see if that fixes it

Check how fast (if at all) the plunger on the side stand comes back into place. Lube if able.

I'm betting this is your issue (side stand relay)

 

If the Safety Relay got replaced by a generic power relay, ... the Bike is going to act like it's possessed.

IF you have the Bike IN GEAR with the CLUTCH LEVER PULLED and the START BUTTON PRESSED and nothing happens, ...
But ... The STARTER ---> WILL ENGAGE ---> with the START BUTTON PRESSED and the CLUTCH LEVER ---> RELEASED

The Safety Relay has been replaced with a Non-Safety Type Relay.

The LOAD and Switching are different in the two relays

Safety:

[+]---[+]
>
[-]----[-]

Generic:

[-]----[+]
>
[-]----[+]

 

It didn't "fix itself."

More than likely, the sidestand switch is flaky-- it "thinks" the stand is down when it's not.

Very common due to where the switch lives.

If the rest of the "neutral" circuit functions (like the light being on when it's in neutral) then it's not that.

 

At least once, every 25-years ... the Sidestand Switch requires cleaning.

Unplug and remove the Switch.
Remove the rubber boot.
Undo the Activating Rod Sections

Spray the "Guts" of the Switch with Electric Parts Cleaning Spray.
Exercise the Switch with the Rod whilst spraying.
Clean the Rod.
(If the Rod is oxidized ... chuck it in a drill and refinish it with 800 Grit)

CLEAN the Kickstand Pivot "Tunnel" where the Rod fits.
Spray with Carb Cleaner or Brake Kleen
Twist some ScotchBrite in the Hole.

Put the whole thing back-together.
Put two drops of Oil in the Kickstand Hole to lube the Activator.

Revise the Cleaning Schedule to "Annually"

 

All the while being very careful with the rubber boot which is more likely than not cracked or split in more than one place and not obtainable.

I've had really good luck painting cracked "boots" with liquid electrical tape.

 

+1 on the s-stand switch.
Even though I did as Rick advised, It still gets a bit "sticky"
at leased once every 14/16 monthes or so.
Now I clean it out at the same sched as valve adj-twice a year.

 

Rick has the right idea here, annual service or factory scheduled maintenance on our vehicles as many items get overlooked (guilty here).
I made up folders for each vehicle we own including motorcycles and can
see at a glance which items are due when. Now I just have to remember
what I rode , and when I rode it.

 

Good point. I keep log books for all of my bikes, it saves me from having to actually remember what I did last and when.

 

hello, new to site/forum, i have an 82 xj750 maxim & having the same type of symptoms. a friend of mine more familiar with metric bikes than i am, advised me that it sounds like the clutches are seized due to the bike sitting for a while prior to me owning it, even though i drove & shifted fine for about a month after i got it. not the problem, clutches removed, inspected, all in good shape, suprisingly. now, it starts in neutral, but when i shift into first, it dies. i was advised to bypass the side stand switch, not sure how, 3 wires, blue, green, & black, what do i connect to what, to bypass so i can ride again ??? advice much appreciated. =)

 

I agree the side stand switch is the most probable cause.

I had the side stand switch actuator extension off my bike for years and don’t recall precisely why. I think for same reason – side stand switch becomes intermittent.
With the extension removed the switch is permanently in position as if kickstand is up. I re-installed the actuator extension the other day as a test of my sanity. Switch worked properly. But for how long? Who knows? It will most like fail again while hundreds of miles from home at night in the cold and rain.

I never liked that while putting down side stand with bike running in gear turned off ignition leaving ignition key on and headlight lit. Too easy to walk away from bike thinking it’s turned off. Side stand down before reaching for the ignition key I feel is safer and normal action for me. So I need to remember every time to turn off the key after bike is already not running. (Too much thinking for this simpleton)

WARNING: Elimination (bypassing) of factory safety mechanisms can be dangerous.

So after analyzing the wiring diagram for my bike (Seca 750), and performing some tests.

The side stand switch controls only the side stand relay and the computer monitor display of STND, it is not involved in the starting circuit. The clutch switch and the neutral switch control the starter circuit cut-off relay.

Three wires come out of the side stand switch and lead to a 3-port connector beside the battery case.
(Black to ground, Blue with Yellow trace to side stand relay, Green with Blue trace to computer).
When side stand goes up (riding position), the switch connects all 3 wires together (i.e. the two other wires to ground)

I made a 3-wire jumper for the connector so as to bypass the side stand switch. My reason for wanting to do this is the side stand switch completes (closes) the circuit when the side stand goes up. That worries me. If the switch fails to make clean contact, the engine will ‘die in gear’. Fixing the side stand switch roadside could be difficult. I prefer a reliable running bike over a pesky flaky safety mechanism.

Another way to eliminate the side stand switch is to unplug the side stand relay (under gas tank near coils on left frame tube 4-wire connector). That relay is open circuit while engine is running. This way, if the side stand switch fails to complete circuit, the STND warning will display, but engine will run in gear regardless of position of side stand. Jumper Black wire to Green with Blue trace wire on the unplugged side stand switch 3-wire connector-wire harness side to extinguish the STND display.

 

got'cha ! thank you for the help, made a 3 terminal jumper for the plug near the starter solenoid for the sidestand safety switch, starts & runs like a champ again ! i fig'd it was somethin simple & silly, i just didnt want to go jumping the wrong wire & fry out some other electrical part.

 

well of course it did not fix it's self that's why I think it is scary. anyways when I was checking out the kick stand switch I also cleaned it ( the rubber boot was not cracked or torn in any way )

IMO this cleaning has fixed the problem how ever I would have liked to see it not working with my multimeter. anyways just going thew the joys of owning a 25 year old bike

 

You Guys a Genius..... I just had a rebuild on my 81 and have been fighting this for 2 days. Came here and presto. Such a rookie mistake on my part but thanks guys. It takes a village to keep these things running.