Tri-Spark question

YING · 2026-08-14T06:01:25-0600

After 5 years of absolutely no problems with my system I have a question that I can’t solve.They tell you to check the air gap but no answer to correct it.After doing all the tests which had the proper results,I took the stator off and found that the rotor was brushing the screw heads that hold the unit to the aluminum plate. I know this is caused by the end float of cam but don’t want to dismantle a great running machine to correct this. I cam thinking about putting a very thin washer between the plate and the casing to keep it from hitting.Any suggestions on this would be appreciated.
Thanks,Mike
Disregard the other picture

Fast Eddie · 2026-08-14T06:15:05-0600

Washers should work IMHO

concours · 2026-08-14T06:50:34-0600

Yep, shim it with washers, Mike. You could also cut some plastic shims from an old oil bottle or antifreeze bottle. Little dab of glue to hold them in place will make it easier while installing.

velo54 · 2026-08-14T07:32:33-0600

Mike, I just assembled my trispark and the rotor diameter is not large enough to touch those screws. You may not have a problem. Should be a 2mm gap. You won't have anywhere near 2mm end float on the cam. Graham

YING · 2026-08-14T07:55:51-0600

velo54 said:
Mike, I just assembled my trispark and the rotor diameter is not large enough to touch those screws. You may not have a problem. Should be a 2mm gap. You won't have anywhere near 2mm end float on the cam. Graham

Graham,
The rotor is the only thing that could be hitting those 2 screws as shown in the picture. I have the 2mm gap when all assembled.What else could be rubbing against it? I did both of the test procedures and all is correct.
The bike was running fine until I pulled into the garage and then died like a blown fuse and would not re-start.All wiring was checked right from the ignition switch and am getting proper voltage,etc.The rubbing on the back of the plate was the last thing I checked.
I will try to shim it out to see if that is my problem as I really like the way the Tri-Spark works.Never been touched in 5 years.Thanks for your input.
Mike

YING · 2026-08-14T08:41:49-0600

YING said:
Graham,
The rotor is the only thing that could be hitting those 2 screws as shown in the picture. I have the 2mm gap when all assembled.What else could be rubbing against it? I did both of the test procedures and all is correct.
The bike was running fine until I pulled into the garage and then died like a blown fuse and would not re-start.All wiring was checked right from the ignition switch and am getting proper voltage,etc.The rubbing on the back of the plate was the last thing I checked.
I will try to shim it out to see if that is my problem as I really like the way the Tri-Spark works.Never been touched in 5 years.Thanks for your input.
Mike

Graham,
I just took it apart again and seeing you are correct on this that the rotor is not hitting the plate!Not even close. I guess my problem is somewhere else as the unit passes their 2 tests. I am going to isolate the wiring and run a basic circuit with only the ignition circuit working off the switch.It was running great all day until I pulled into my garage! The gods were with me as it saved me from waiting for a tow truck on a hot day.
I don’t know if those 2 screws were filed before I put it in originally.They could have been done with a file
Thanks again for showing me my error.
Mike

Tornado · 2026-08-14T12:06:20-0600

I had some weird electrial issue, random fuse blows etc yet poking around with test lamp found no issues. Ultimately turnout to be the multi bullet connector under the tank had developed a split in the rubber btwn two connectors, letting then short out at certain vibrations. This was a new replacement multi connector block...so do not trust them at any age. I made up a set of doubles and singles to eliminate the multi block...also makes for a narrower install which helps a lot in that area.

concours · 2026-08-14T13:59:53-0600

Tornado said:
I had some weird electrial issue, random fuse blows etc yet poking around with test lamp found no issues. Ultimately turnout to be the multi bullet connector under the tank had developed a split in the rubber btwn two connectors, letting then short out at certain vibrations. This was a new replacement multi connector block...so do not trust them at any age. I made up a set of doubles and singles to eliminate the multi block...also makes for a narrower install which helps a lot in that area.

True story. "New doesn't necessarily mean good"

Cuppy · 2026-08-14T17:25:11-0600

YING said:
Graham,
I just took it apart again and seeing you are correct on this that the rotor is not hitting the plate!Not even close. I guess my problem is somewhere else as the unit passes their 2 tests. I am going to isolate the wiring and run a basic circuit with only the ignition circuit working off the switch.It was running great all day until I pulled into my garage! The gods were with me as it saved me from waiting for a tow truck on a hot day.
I don’t know if those 2 screws were filed before I put it in originally.They could have been done with a file
Thanks again for showing me my error.
Mike

I have also been having issues with my Trispark that were only happening when hot. No spark until after I let the bike sit. Then last week it just quit like the switch was turned off a mile down the road. I have been through all tests on wires and connections. I haven't actually measured the 2mm gap but it looks like more than 1/16" and less tahm 1/8" so I assumed it was ok. I have seen through an AI inquiry that too much of a gap can cause a no start when hot. Otherwise the bike starts and runs flawlessly.

YING · 2026-08-15T01:45:51-0600

Tornado said:
I had some weird electrial issue, random fuse blows etc yet poking around with test lamp found no issues. Ultimately turnout to be the multi bullet connector under the tank had developed a split in the rubber btwn two connectors, letting then short out at certain vibrations. This was a new replacement multi connector block...so do not trust them at any age. I made up a set of doubles and singles to eliminate the multi block...also makes for a narrower install which helps a lot in that area.

Tornado,
I have the same connector under the tank that I will check today as it sounds like you had the same gremlin as I am experiencing.Bike running fine and then all goes blank.

Tri-Spark question

YING

Pittsboro,NC

Fast Eddie

concours

velo54

YING

Pittsboro,NC

YING

Pittsboro,NC

Tornado

concours

Cuppy

YING

Pittsboro,NC

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