LA_Dog
Go Fast, Go Faster
Hello all- finally got my tins back on the bike and fired her up for a test ride. In short, bike runs great until it warms up and then it runs like a lawnmower. both cylinders firing but the "crispness" is gone and it runs stumbly, sort of like running a very bad tank of gas. It idles ok but the idle cadence is different once the issue pops up. When bike is cold the idle is very perfect and "lopey" as it should be with the 600 cam. giving it part throttle or full throttle makes no difference. I have fiddled with air / fuel mix and it is not that.
I have checked all the usual suspects- getting spark, no intake leaks or leaks around carb, voltage is good from charging system, pulled bowl on carb / checked all jets, float level, fuel delivery system is good, carb adjustments etc...
In looking at the plugs, they are on the whitish side on the insulator but not indicating lean condition (new plugs only have a few miles on them tops). Electrode is tan. the plugs smell a bit gassy but very faintly, plugs are not black or sooty so not indicating rich either. both plugs look equally the same.
Bike has 3800 miles on it and it ran very strong before I had it sitting for 2 months while tins were off. previous set of plugs showed perfect burn on both cylinders. it had an older G carb that was slightly under-jetted with the fixed air bleed, and was rather notchy on part throttle so I bought one of Bob's XXX carbs.
Stuff I have done to bike while it was sitting:
All new fuel lines
changed all fluids
Pingel high flow petcock
New Landmark vented gas caps (yes I checked the vents- all good!)
New dual dyna coils, new NGK plugs and Twisted wires
Recently re-lined tanks (professionaly done)
New XXX carb (32 intermediate jet / 76 main jet / 060 main bleed / 040 intermediate bleed
Bike is direct wired with no EHC, wire connections are all good, fuses / breakers are all good - Bike has a Crane HI4 unit (Crane unit is at least a few years old) - set to Race Mode, 1/2 way on advance, -2 for rear cylinder
I can reproduce the issue by letting the bike warm up for 3-5 minutes.
Any ideas? Maybe failing cam sensor on the HI4 module? My TP motor has the cam sensor in nose cone. This is killing me. :bang:
I have checked all the usual suspects- getting spark, no intake leaks or leaks around carb, voltage is good from charging system, pulled bowl on carb / checked all jets, float level, fuel delivery system is good, carb adjustments etc...
In looking at the plugs, they are on the whitish side on the insulator but not indicating lean condition (new plugs only have a few miles on them tops). Electrode is tan. the plugs smell a bit gassy but very faintly, plugs are not black or sooty so not indicating rich either. both plugs look equally the same.
Bike has 3800 miles on it and it ran very strong before I had it sitting for 2 months while tins were off. previous set of plugs showed perfect burn on both cylinders. it had an older G carb that was slightly under-jetted with the fixed air bleed, and was rather notchy on part throttle so I bought one of Bob's XXX carbs.
Stuff I have done to bike while it was sitting:
All new fuel lines
changed all fluids
Pingel high flow petcock
New Landmark vented gas caps (yes I checked the vents- all good!)
New dual dyna coils, new NGK plugs and Twisted wires
Recently re-lined tanks (professionaly done)
New XXX carb (32 intermediate jet / 76 main jet / 060 main bleed / 040 intermediate bleed
Bike is direct wired with no EHC, wire connections are all good, fuses / breakers are all good - Bike has a Crane HI4 unit (Crane unit is at least a few years old) - set to Race Mode, 1/2 way on advance, -2 for rear cylinder
I can reproduce the issue by letting the bike warm up for 3-5 minutes.
Any ideas? Maybe failing cam sensor on the HI4 module? My TP motor has the cam sensor in nose cone. This is killing me. :bang:
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