Hard starting

[BigRed]

Hey, folks.

I've got an '80SG with an engine from a '82-84XJ. At least the engine serial number suggests it's an XJ engine... there's a vacuum/mechanical advance under the timing plate... I thought XJs used electronic timing. It also appears to have the YICS path (there's a plug under the intake on the engine).

Good news: I've got a safety, so the bike is technically ready for the road.

Bad news: It doesn't like to start for two reasons:
1) Sometimes the starter will crank the engine, then the teeth will disengage, and I'll hear it spin up really fast. Once I let go of the button, I can hear it spin down, then engage again. I know this problem is in my starter, but is there a fix, or am I looking for a replacement?

2) When it's cranking well, it still doesn't like to start. I might spend 2 minutes cranking and playing with the choke and throttle before it will fire up. Last night, it sounded like it was trying to start on one or two cylinders... it would chug as long as I was holding the starter button, but didn't want to get going for maybe 10-15 seconds. Once it does fire up, it runs well and idles well.

I hooked up my timing light, and it would go off sometimes while cranking, but not all the time, so I figure I've got a weak or intermittent spark problem while starting. Once it's running, the spark is consistent.

I read the "troubleshooting a bike that will crank but won't start" tech tip. Where is the ballast resistor? I've got a bunch more troubleshooting left to do, but I thought I'd start with the ballast resistor.

So far, I've fixed the pick-up coil wires, and I've cleaned the carbs and set the float heights. Anything else obvious left to do? My next step will be replacing the fuse block (I've got one of T.C.'s) and cleaning all the connectors. I'll check all the resistances in the ignition system while I'm at it.

[DGXSER]

Provided you made sure to clean up the enricher path through the float bowls good, I'd say your on the right path.

I would suggest the fuse box next, and then check for voltage and resistance on the coils and such. What TCI is under the seat? Does it have a green label that reads 10M as the first three digits, a yellow one that reads 4RO, or no label but 2H7 and some numbers molded into the body?

The XJ series bikes did not use the ballast resistor. But if you have a mech adv, and you have the 2H7 TCI, then your bike is setup like an 80 or older bike. The coils also vary from 1.5 ohm coils to 3 ohm coils on the 81 and up models, that is why the resistor was eliminated.

[BigRed]

Yep, the enricher circuit was good and clean.

I'm pretty sure that it's a 2H7 TCI. Was the 2H7 used on the '80SG or '82XJ? It's likely that whoever changed the engine swapped the pick-up assembly and kept the '80 SG ignition system.

[newc4]

My 78E was a very hard starter. I finally decided to check the spark plug gaps and it had been a while since I did so. Each plug's gap was filled with gunk.

Sometimes its the simplest things.

Darrell

[WMarshy]

Provided you made sure to clean up the enricher path through the float bowls good, I'd say your on the right path.

I would suggest the fuse box next, and then check for voltage and resistance on the coils and such. What TCI is under the seat? Does it have a green label that reads 10M as the first three digits, a yellow one that reads 4RO, or no label but 2H7 and some numbers molded into the body?

The XJ series bikes did not use the ballast resistor. But if you have a mech adv, and you have the 2H7 TCI, then your bike is setup like an 80 or older bike. The coils also vary from 1.5 ohm coils to 3 ohm coils on the 81 and up models, that is why the resistor was eliminated.

Isnt there an issue with missmatching the ignition components between the XJ and XS? Thought you had to use the coils, advance, and TCI from the proper engine year? Or this is all a dream as its time for bed.

[BigRed]

I've checked the plugs, and they looked good. I've got new ones to put in, but the new ones have resistors, so I'm going to get new plug caps without resistors so as not to double up.

If I've got mix-and-match ignition components, then I expect that would be a problem, but AFAIK, all my ignition components are from the '80SG. I don't think it should matter what engine it's hooked up to as long as all the ignition components mesh. I would expect to have problems if I've got a TCI that does electronic advance combined with a vacuum advance, or a ballast resistor in series with coils that don't need it. Having said that... is the 2H7 TCI from an XJ? That could be my problem, or at least part of it.

Oh yeah... where is the ballast resistor? I need to check if it's there or not, and if it works.

Thanks for all the help; you guys are quick!

[Rasputin]

My ballast resistor was under the tank on the left hand side and it looked like this

[petejw]

the starter problem sounds like your starter clutch
is slipping, its an engine tear down to repair
it properly if its worn, synthetic oils/ cold weather/ thicker oil
and a weak battery are some things that can make the matters worse.
mine would start fine in summer then as it got colder
could take anything upto 20 min to get it started.

have you pulled the plugs and check for spark
on each of the cylinders?

[BigRed]

the starter problem sounds like your starter clutch
is slipping, its an engine tear down to repair
it properly if its worn, synthetic oils/ cold weather/ thicker oil
and a weak battery are some things that can make the matters worse.
mine would start fine in summer then as it got colder
could take anything upto 20 min to get it started.

have you pulled the plugs and check for spark
on each of the cylinders?

That's really sh!tty news about the starter clutch being an engine teardown. I just put synthetic in it becuase I couldn't find a suitable viscosity mineral oil. Should I get it out? I've only gone about 5km on this oil. You said to "properly" repair it, it's an engine tear down... Is there in "improper" repair? I'm not afraid of pulling an engine... It's just that I've already done it on my other bike this spring.... I wouldn't mind a bit of a break

I did check for spark on each cylinder after I did the pick-up coil wire fix, and it was there. A couple days ago while it didn't want to start, I checked for spark with my timing light on cylinders 1&2, and spark was intermittent at best. It seems that I might get a spark immediately when I push the starter, and right when I release the starter, but not very many sparks while I'm holding the starter button. I guess this means that the starter motor is using enough power that I'm not getting a spark?

[XJOK2PLAY]

That's really sh!tty news about the starter clutch being an engine teardown. I just put synthetic in it becuase I couldn't find a suitable viscosity mineral oil. Should I get it out? I've only gone about 5km on this oil. You said to "properly" repair it, it's an engine tear down... Is there in "improper" repair? I'm not afraid of pulling an engine... It's just that I've already done it on my other bike this spring.... I wouldn't mind a bit of a break

I did check for spark on each cylinder after I did the pick-up coil wire fix, and it was there. A couple days ago while it didn't want to start, I checked for spark with my timing light on cylinders 1&2, and spark was intermittent at best. It seems that I might get a spark immediately when I push the starter, and right when I release the starter, but not very many sparks while I'm holding the starter button. I guess this means that the starter motor is using enough power that I'm not getting a spark?

It's sounding like you may have a Frankinmotor there...

Pickup coil wire fix??? Not if it is an XJ motor...

XJ's have the YICS, the RH side cover says 'YICS' on it. They have electronic timing... LH side timing plate is bolted solid w/ 3 screws... they have a vaccuum advance device under the gas tank, depending on the amt. of vaccuum applied, varies voltage sent to the 10M TCI unit under the seat... totally different timing setup than the XS.
You must swap the ignition system totally, one way or the other, to use one motor in the other type bike.
XJ's also have a cable operated choke lever on the LH handlebar.... XS's use a manual lever on the LH side of the carbs.

The 2 engines are basically the same... XJ's are just a little more detuned than the XS's... (Timing approach, carbs, cams...)

Look for the TCI unit... if it is an XJ motor, and you don't have the Vac Sw. under the tank, or a 10M TCI... but you do have the XJ type ignition plate, or it has the YICS system... that's probably one of the main reasons it's not starting / running right.

Then of course, carbs would be the next thing to look at...

As stated, if it's a bad starter drive, you gotta split the cases to fix it. Sorry.

Also.... you don't want to run any oil in these engines that have friction modifiers.... There's PLENTY of info here about that.... clutch becomes the issue then... they don't like it and begin to slip.
HTH's.
Bob

[psycoreefer]

I did check for spark on each cylinder after I did the pick-up coil wire fix, and it was there. A couple days ago while it didn't want to start, I checked for spark with my timing light on cylinders 1&2, and spark was intermittent at best. It seems that I might get a spark immediately when I push the starter, and right when I release the starter, but not very many sparks while I'm holding the starter button. I guess this means that the starter motor is using enough power that I'm not getting a spark?

This part jumps out at me, I had the exact same problem on a honda shadow I had, turns out the (on that bike) CDI box had to have a minumum of 10V to work properly, when I pushed the starter button on a weak battery my power at the CDI would drop below 10V and I'd get weak, erratic, no spark. 2 things to try, back probe the power wire on the TCI and watch the voltage while the bike is cranking, if its much lower then 11V I'd guess that's your problem. The fuse box fix might solve the problem, or a new battery might as well.

On my shadow I finally figured it out because it would start every time if I pushed it.

[DGXSER]

There are ways to mix and match the components if you know what your doing, kind of.

The XJ system stock has no mech or vac advance under the ignition cover where the pickups are. Typically, it does not need the wire fix, because they do not get flexed due to no mech or vac advance operation. However, it would not be out of the question but very rare for it to require that repair. The XJ system has the vac and mech advance built into the 10M TCI it uses. It also uses 3 ohm coils and therefore no ballast resistor. IT does have a vacuum module under the tank that sends a signal to the TCI though.

The 81 4RO TCI has the mech adv built into it, but not the vac adv. that is still there underthe ingition cover. It is also not very likely to need the pickup coil repair due to no flexing of mech adv. But again, it is not unheard of. The 81 system also uses 3 ohm coils and no ballast resistor. It has been reported more than once here that an XJ system will run well on the 4RO TCI. You will just lose some fuel efficiency of the vac adv.

All the 78-80 models used the 2H7 TCI. These systems use a mech and vac adv under the ignition cover with the pickup coils. Typically, these systems used the 1.5 ohm coils and the 1.5 ohm ballast resistor. They were also more prone to needing the pickup coil wire repair due to the XSive flexing of the wires from the mech and vac adv.

In this case, having the mech adv and the vac adv, and the 2H7 TCI you should be set.

Now, one of the older model owners or electrical gurus that I am not might be able to tell us if you could use the XJ 3 ohm coils with the 2H7 system and eliminate the ballast resistor.

I would agree with psycho on the low battery issue. Check that first. I also agree on the synthetic oil possibly being your issue on the starter clutches. Those and the actual clutch rely on friction to work. Synthetic oil is of course specifically formulated to eleviate or eliminate friction.

[BigRed]

Yes, it is a bit of a Frankinmotor, but if I read you right, I think it's done correctly. The vacuum advance is under the timing cover on the LH side of the engine, and it's a 2H7 TCI. So, I think I've got an XJ motor with a complete XS ignition (assuming I have a ballast resistor). It does seem to have the YICS system, but from what I understand, that shouldn't affect spark. I believe the carbs are also from an XJ, as they are set-up to receive a cable, but there is no cable. Until I find one, I'm just holding the slide with my finger until it's warm enough to ride. Since I've cleaned/adjusted the carbs, it only takes a few seconds before it doesn't need any choke so long as I've got my hand on the throttle to keep it from idling down to a stall. After about a minute or two of warm-up, it will idle just fine.

I didn't know that the XJ was detuned... are there any simple mods I can make to bring the HP up to XS levels? I guess I should focus on getting it to start reliably before I move on to HP mods.

As far as splitting the cases... that may ruin my week. For now, the starter does catch enough to get it running even though it's a hard starter, so I'm going to try to solve my spark issue, and then wish for the starter clutch problem to solve itself. I'll double check that my oil doesn't have any friction modifiers. I'm pretty sure it was Mobil 15w40 Synthetic.

It was mentioned that a weak battery could make the starter clutch problem worse... maybe I'm really lucky and all I need is a new battery, and everything will be solved...... maybe the new battery will even fix the crack in my windshield

[Crazcnuk]

Easy enough to test, just hook booster cables from your car battery to the bike battery and try it.

Don't start the car. The bigger battery will have no problem providing full voltage while cranking the starter over.

If it spins better and gives good spark doing this, then you know a new battery is needed.

[BigRed]

Good point; I'll try that. It starts great when hooked up to a running car, but it didn't want to start last time I tried to boost it without running the car. I could have flooded it while trying to start it before boosting though.