exhausts glowing red hot?

[whitenight639]

Long story short - Bought bike, wouldn't idle without choke and exhaust headers would glow red hot within a 3-4 minutes idling, took carbs off and blew out pilot jets with compressed air, cleaned out a little oil from air box. Bike now starts and idles without choke, it was a little irratic so I replaced Carb boots / rubbers. 


When I took my carbs apart I took out the pilot air screws by accident, I have put them back to 2 turns out. Anyway now the bike idles but sounds rough and when revved it takes a while for the revs to drop back down, it didn't do that before the revs fell quite sharply when throttle released.


Anyway my main issue is now number 1 and number 3 exhaust headers are cool, eg number one is about 35 Degrees C after 2-3 minutes idling and 2 and 4 are about 160 Degrees C, number 3 be around 60-80 Degrees. Anyway I dont think number one is firing, when I removed number one spark plug it was black and wet and there was a good spark, So I don't know what to do, Compression test / Carb sync, bench sync / valve clearances? I will have to buy the kit for this stuff and money is tight atm as I'm paying for my mod 2. The bike revved and sounded fine / much nicer on choke before I looked at the carbs but it wouldnt idle without choke, (even after adjusting the stop screw). I've checked float heights they are ok by my eyes so I don't know what to do next, I really hope its nothing serious.


The first issue I had after re-installing carbs was no fuel to right two carbs which fixed itself after a few hours sat on prime.

Could this be ignition timing  or coils / ht leads? (I bought a cheap timing light on ebay but didn't work when it arrived, its gone back).

How hot should exhausts get after a few minutes idling with still air?



92 Diversion 600.  

[showaddydadito]

Sorry I can't offer advanced technical stuff here, but for certain the downpipes should be too hot to touch within seconds of the engine starting.

[GAv]

Could the needles be sticking, to be honest I have no idea about the Divvy ones.I'm not trying to rub salt in the wounds but my900 starts and runs smoothly so I leave it be.(the old adage if it ain't broke don't fix it)
if it is standard Jap Mikuni fair(they used to copy Amals) ,then sometimes the needles give the impression they have seated in the ventures,but are sitting the wrong way around in the slider groove. Or the cable has got caught in the spring.
Even the cables can activate even if not right in the the top round retainers that that they sit in, so the return spring and main needle jets aren't fully compressed with the throttle off.

[showaddydadito]

Apr 16, 2015 12:48:33 GMT GAv said:

(the old adage if it ain't broke don't fix it)

This is the Diversion forum - we march to a different drum here: If it ain't broke, keep on fixing it until it is.

[CD]

Poor fuel
Burns slowly
Heat escapes down exhaust
Pipes get very hot
Weak mixture - too much air or poor fuel - pipes get very hot
Late ignition spark - pipes get very hot
Check TPS

[whitenight639]

Thanks Guys and Gals, I had another look and sniff at number one spark plug and ran it for a sec without it in (it ran the same) but I think its just oil on the plug I mistook for fuel, with the plug out and my hand over the hole there was no dampness or smell of fuel from number one cylinder so it seems dry of fuel to me, and it sucks and blows well (best I can tell without compression tester) so I will revisit carbs and strip them properly (and chuck them in the ultrasonic at work when boss isn't looking), thanks for your suggestions. :-)

[whitenight639]

Just an update for others with similar problem, I looked at the pilot jets again and the hole was really really tiny, when I compared them all the holes were different, So I poked some wire through them, there must have been crud on the walls of the holes because they are all the same now and bike runs on all 4 now :-)

now I think I will look at replacing the vacume fuel pump with a suitable electric one.

[CD]

The Divvie 900 or Fazer 600 pump does the job