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Discussion Starter #1
now, i dont know much about bikes and all, but how often do ignition coils go bad?

i'm having difficulties to start my cb650 (starter is clean, new battery, carbs have been rebuilt, so i figured it was the ignition?)

CB650, FauxCatiFT500
 

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Even used coils can run $25 - $50. Often, there's nothing wrong with them.

Did you pull a plug, turn it over and check for blue spark?

More than likely its the connection where the plug caps meet the plug wires. In many cases, the caps thread right into the end of the wire and this connection gets worn after a while. Take them off, snip a 1/2" or so off the plug wires, screw the caps back on and recheck for spark using some fresh plugs.



Honda go sideways!
 

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look for wax seeping from your coils. most of the time, the coils will let the bike start, they just heat up and start to crap out later. check the plug ends, and first make sure you have spark. if it started before the carbs were rebuilt, and you didnt have someone who knows what they are doing for sure, id look there.

if it ran before, its probably not coils.



jc


aaron, send my wheel.
 

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Discussion Starter #4
ok, so by elimination we figured out (between a few friends and i) that it's running rich. the main reason is that it never works with full choke and only half to a third choke is the only way it'll start. plus, when i was up in york on tuesday the starter relay took a shit on me and i had to have my friend push me down the hill to get it started.

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quote:
ok, so by elimination we figured out (between a few friends and i) that it's running rich. the main reason is that it never works with full choke and only half to a third choke is the only way it'll start. plus, when i was up in york on tuesday the starter relay took a shit on me and i had to have my friend push me down the hill to get it started.

CB650, FauxCatiFT500
Those 650s are known for having pulse generators go bad. The bike will lose power or be hard to start because the spark timing is no firing properly. Also everything on those bikes passes through the starter relay so if that has started to go bad (by not engaging the starter) then it can play all sorts of havoc with your honda igntion system.

IIRC the 650 should have CV carbs which if set properly are hard to go out of adjustment without a good jarring (their design also compensates for engine needs). If you think it is running rich and you haven't dropped the bike or messed with the carbs lately I would guess your pulse controller is going all screwy and your electrics are about to take a huge shit.

I had a pulse controller go bad on the 79 DOHC cb750f (which uses the same design ignition system as the 650) and basically went from doing 110mph on the L.I.E. no problem to 65 mph pinned Wide Fucking Open . I managed to limp home but the bike was incredibly hard to start without messing with the choke, because the pulse controller was throwing a weak and out of time spark. Fixed it and the relay (they seem to go bad together) and the bike runs like a raped ape.

Edit: BTW stick to traditional methods of diagnosing rich and lean conditions (the best is the exhaust - you'll smell it) instead of guessing because a choke is acting funny. It is enteirly possible it is running rich because of the carbs (jets tend to fall out on these bikes and rattle around in the float bowl too so you may want to check that) or it can be running rich because of something else. With hondas from the late 70's early 80's most of the problems are electrical (unless you have been wanking on it and managed to get the timing chain to eat the motor which has happened) so I always default to checking that first. BTW, you can replace the relay with one from a CBRrr (look for my post on starter solenoids on the cb1100f.net board) with a little mod, and also put a cbr right bar control and it makes the relays last a lot longer, those early 80's relays are a bad design and a lot of guys have probelms with them blowing.

Edited by - geeto67 on Mar 22 2007 1:22:19 PM
 

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also, if its ig related, and running like shit, it will look rich.

jc

jc


aaron, send my wheel.
 

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Discussion Starter #7
hot damn! well thank you lads!

i'll take a look at it this weekend. the reason i thought it was running rich is because i've got 1 friend who went to MMI and one other who's been into bikes since he was 4 (parents had a dealership) both said that it seems to be rich. so, i trusted 'em. but now, i'll have to throw a beer bottle at them.....

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Discussion Starter #8
damn, now it just starts with a push of a button..... did nothing to it, nothing!

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damn, now it just starts with a push of a button..... did nothing to it, nothing!

CB650, FauxCatiFT500
you're gonna need to hunt down that problem anyway, unless you like waiving to the traffic from the side of the road.

since it is running well, you can start to check the wires and see if it will cause the condition to come back. Of course it could have also been a carbon fouled plug (hondas foul #1 when they sit - it is where the side stand leans to) which could cause the pipes to load up with unburnt fuel and by running it you could have cleaned it up a little.
 

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Check for a dead short. A likely place to start is where the harness runs up next to the steering head and into the headlight. Turn the bars hard over right and left while pressing the starter switch. I've had ignition "hot" wires ground themselves out to the brake light wire--rubeed themselves bare inside the loom. The quirky shit you're dealing with sure sounds electrical.



Honda go sideways!
 
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