Author Topic: 1977 cb550f w/ aftermarket fuel injector dies ever 25 freeway miles  (Read 1843 times)

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highwayhijinx

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I just recently took this bike on the freeway for the first time since buying it.  It has run well, with no problems, for about 2 weeks just running around town.  About 25 miles after i started on the freeway, it started sputering and backfiring and then the throttle stopped working altogether, then it completely shut off, but the electrical still works.  After waiting about 10 mintutes, starts right up, runs well, but then dies the same way 25 miles later, then the same thing 25 miles later.  After the next 25 miles it seemed okay, then i switched on my signal light, the bike backfired simultaneously with the switch being turned on and off twice.  Pulled off the freeway, then bike died, and wouldn't start for awhile.  After 25 more miles i let the bike rest, then it ran for about 40 miles, at normal, not freeway speeds, and had no problems for the rest of the night.  In the morning it ran for about 50 miles at 70+ mph, then died after i pushed the engine to anout 90mph.  It died numerous times within the next 100 miles, although no longer at 25 mile intervals.  It is also having problems just driving around city streets now.  Fuel filter seems to be letting fuel through fine, hoses are good, tank ventilation seems good (tried leaving the cap unscrewed for awhile)  There is an aftermarket fuel injector installed in place of points, maybe this is the problem?  anyone ever heard of this?

Offline Sam Green Racing

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Re: 1977 cb550f w/ aftermarket fuel injector dies ever 25 freeway miles
« Reply #1 on: August 19, 2006, 06:25:50 PM »
Can you post a picture of this,? it sounds like you are talking about an electronic ignition system, not fuel injection.

Sam.
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Dirtman666

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Re: 1977 cb550f w/ aftermarket fuel injector dies ever 25 freeway miles
« Reply #2 on: August 19, 2006, 08:45:11 PM »
Sounds like you have fuel getting into the ignition system ???

I would replace the kanewten valve and change the air in the tires - That should fix your problem!!!


Just kidding ;D ;D

Offline nickjtc

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Re: 1977 cb550f w/ aftermarket fuel injector dies ever 25 freeway miles
« Reply #3 on: August 19, 2006, 08:53:15 PM »
Maybe a tiny fracture somewhere in the wiring of the electronic ignition...once everything gets really hot the break opens up; then after it cools down there is continuity again. I believe the diagnostic procedure is to get an aerosol of something cold (not sure what) and spray it on various parts of the circuitry when things die. The cold makes continuity so when you find the exact location of the break you can set about fixing it.......or something like that.
Nick J. Member #3247

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"That which does not kill us reminds us to wear proper motorcycle clothing...."

Offline Sam Green Racing

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Re: 1977 cb550f w/ aftermarket fuel injector dies ever 25 freeway miles
« Reply #4 on: August 19, 2006, 08:55:15 PM »
Good job you said "just kidding" he might have tried to do it after asking what a kanewten valve was ;D

By the way,....what is a kanewten valve ??? ;)

Sam. :D
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike

Offline nickjtc

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Re: 1977 cb550f w/ aftermarket fuel injector dies ever 25 freeway miles
« Reply #5 on: August 19, 2006, 09:17:06 PM »
Good job you said "just kidding" he might have tried to do it after asking what a kanewten valve was ;D
By the way,....what is a kanewten valve ??? ;)

It's from the same parts box that the muffler bearings come from.
Nick J. Member #3247

2008 Triumph Tiger 1050
1977 Suzuki GS750

"That which does not kill us reminds us to wear proper motorcycle clothing...."

Offline Sam Green Racing

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Re: 1977 cb550f w/ aftermarket fuel injector dies ever 25 freeway miles
« Reply #6 on: August 19, 2006, 09:22:39 PM »
Damn clever those Japanese Nick ;D ;D ;D ;D
C95 sprint bike.
CB95 hybrid race bike
CB95 race bike
CB92
RS 175. sprint/land speed bike
JMR Racing CB750A street ET drag bike