Stuttering while accelerating?

[Graman]

Sounds like you've got your stuff together. I'm still battling a stuttering problem @ 45k and a bouncy idle. I haven't had much chance to work on it lately. I'm going to have to take another look at those pick up wires again. They look good but I might just splice new ones in anyway.

[motoman]

Sounds like you've got your stuff together. I'm still battling a stuttering problem @ 45k and a bouncy idle. I haven't had much chance to work on it lately. I'm going to have to take another look at those pick up wires again. They look good but I might just splice new ones in anyway.

"look good" does NOT locate internal breakage of wire. your gonna half to two handed pull opposite direction every inch of each wire...a little agressively. Where insulation stretches IS where a break is. Advise NOT to solder a fix either.

[Graman]

Thanks Motoman.
Why not solder? I would of thought splicing a new piece of wire in (not joining the old wire together) and soldering and covering with heat shrink tube the best method. Better than using crimps I thought. I also found a wiring diagram for the ignition system for my model so i should be able to hook my meter up to the connection at my ignition control box and at the pick up coil and check the continuity of each wire as I pull on it.

[motoman]

Thanks Motoman.
Why not solder? I would of thought splicing a new piece of wire in (not joining the old wire together) and soldering and covering with heat shrink tube the best method. Better than using crimps I thought. I also found a wiring diagram for the ignition system for my model so i should be able to hook my meter up to the connection at my ignition control box and at the pick up coil and check the continuity of each wire as I pull on it.

Not necessary.....just tug right smartly every inch of each wire.......can't be that hard to follow sugesstions by those apparently more savvy and BTDT or you wouldn't be askin' in the first place.....then you'll get solid advice where to go from there.

Heat from soldering copper wire(or aluminium) weakens the metal where heated. With constantly moving wires from the advance rotation WILL cause them to break again. Use a naked butt connector, cut it in half to reduce the size of connection, use GOOD crimper tool and not some cheap thing from HF or your local DollarStore. Slide a small piece of quality(pink for size referance)shrink tubing on one of the wires prior to crimping and slide the shrink on there after crimping and shrink it.......done.

You have alot other voltage check locations that NEED to be done also.......not just yet tho.....patience grasshopper.

[motoman]

I have the vacuum gages. Already balanced them.

The previous owner did the work himself, but could have possibly ordered through a dealer and the dealer got the sizes wrong. But if I was going to do the work myself, I'm going to make damn sure the sizes I'm putting in are definitely correct.

CORRECT idle mix settings HAVE to go hand in hand with the sync.....or your pissin' in the wind and a waste of time.

[Graman]

Thanks for the advise Motoman. I was just really interested in your reason why you didn't recommend soldering the joint. I guess I shouldn't have questioned the ultimate guru. I have been working as an electronics technician for 30+ years and have developed some skill with a soldering iron. I plan to use a high wattage gun and make the joint very quickly. This should keep the heat localized to the joint. Then heat shrink it after. If it acts up again I'll know were to look. Besides I only have a cheap crimping tool.

[3Phase]

Good luck!

Graman,

Really! Maybe you'll be one of the lucky ones!

A lot of people that solder the splice on the pickup coil wires end up doing it over again after the splice breaks at the solder joint. It won't take the constant vibration and flexing.

If you follow the wires back inside the insulator sheath on the same part of the wiring harness you'll find the special Orange, Blue, and White pickup coil wires are crimped, not soldered, to the harness wires for the trip up to the TCI too.


.

[motoman]

Thanks for the advise Motoman. I was just really interested in your reason why you didn't recommend soldering the joint. I guess I shouldn't have questioned the ultimate guru. I have been working as an electronics technician for 30+ years and have developed some skill with a soldering iron. I plan to use a high wattage gun and make the joint very quickly. This should keep the heat localized to the joint. Then heat shrink it after. If it acts up again I'll know were to look. Besides I only have a cheap crimping tool.

Good thought.....not happenin' tho.............certified welder, metallurgy training associated with that, certified A&E(automotive/heavy equip.) mechanic, certified hydraulics systems designs and buidling for specialized equipment, high performance engine building and racing, etc...........retired.
Not that it matters.....just sayin'.

Post #49, second paragraph answers your 'why'.

[Graman]

Would you advise joining the original wire at the break making just 1 connection or splicing in a new piece from the coil up into the wiring harness above the clamp?

[motoman]

Would you advise joining the original wire at the break making just 1 connection or splicing in a new piece from the coil up into the wiring harness above the clamp?

One connection, normally the wires aren't FUBAR'ed to necesitate that.
BTW, your electronics experience is most welcome here. The total skill-sets here CANNOT be matched by ANY bike shop or even dealership factory trained techs, and majority of other bike sites. That also goes for alot of other areas besides bikes where expert advice is needed. My other listed bikes site comes close, but still no match for here.

So, for those here that read this and are somewhat 'newbies', best advice I can give is by all means, keep these ole' elevens(and alot of other scoots) out of the 'bike shops' and dealerships.

Bottom line is, if you just wanna ride the classic scoots and have little to no interest on the mechanical/electrical aspect..........you got the wrong bike era in mind.....don't even go there.

[Graman]

To me having a bike you didn't have to work on would be boring. I enjoy working on it as much as riding it. That's why I bought an older bike. More of a hobby than anything else. I like to learn more and more about how it works and how to repair it. I have owned a couple of Yamaha"s in the past. An XS400 Special and an XS650 Maxim. Both fun to ride. So the XS1100 Special is kind of nostalgic and even more fun to ride.

[motoman]

Looks like you found the right bike and site then.

[Graman]

I had a chance to check out the pickup coil wires today. I released the clamps and got the wires out were I could access them over there full length. I tugged on them all down there length firmly and could not feel or see any evidence of a break. No hour glassing in the insulation at all. I went one step further and inserted a very fine sewing pin into the wires right at the pickup coils and checked each wires continuity all the way up to the plug that goes into the ignition control. Also tugging on the wires. No break in the circuit. Resistance in the coils seems good. I was kind of disappointed that I didn't find a break. It would of been the answer to the stuttering problem I was looking for. Oh well the mystery goes on. At least it's a challenge and the bike is still great to ride as is while I hunt for the solution.

[bikerphil]

A simple test you could try to verify that you have strong current powering the TCI is:
With the key on, check the voltage at the red/wht wire solder joint on the solenoid and compare that voltage to voltage present at the fuse box. Anything more than .5 V difference means that kill switch circuit which powers the TCI is ailing.

That was my problem with a low RPM stutter, may help with your higher RPM issue.

[motoman]

Bikerphil's suggestion is good..........but, first I'd pull the caps off plugs, unscrew the cap from wire, cut a good quarter inch(make sure you still leave enough reach to plug) off, re-strip and screw the cap back into wire. That's a known loss of secondary ignition voltage.
The kill switch contacts IS the commom area of lost primary voltage, with the ignition switch being second.
All the plug-ins behind fuse panel, if they haven't been gone thru, cleaned and sealed with a toothpic dobbed bit of dielectic grease on contact plug-ins.
IMO, your issue is still either prim. or sec. ignition voltage issues, not carbs, at this point anyways. Gotta make sure that's all 'golden'(no guessin' use meter for voltage and ohm checking)..........THEN, posible fueling issues.