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From: billybuckshot on 15 Jun 2007 21:09
On Jun 15, 7:44 pm, "Albrecht via MotorcycleKB.com" <u33665(a)uwe>
wrote:
> billybucks...(a)gmail.com wrote:
> >To answer everyones questions: i failed to mention that i replaced the
> >mixture screws. that didn't help. i also inspected where they seated
> >and the was no noticable damage.
> >i've also been through about 6 sets of NGK B8ES plugs, that are
> >constantly being cleaned in the bead blaster and returned back to the
> >rotation. I've also tried hotter B7ES plugs, no difference.
>
> The only carburetor-related thing I can think of is high fuel level in the
> float bowls, making it too easy for the engine to suck up gasoline at idle
> RPM.
>
> When you set the floats at 20mm, were you measuring from the aluminum body of
> the carburetor, or were you measuring from the paper float bowl gasket?
>
> If the gasket is stuck to the carburetor body and you don't want to disturb
> it, subtract 1mm from the nominal float height.
>
> Do you get a nice fat 1/4-inch long blue spark when you hold the lead next to
> the spark plug while the engine is idling?
>
> Do the spark plug electrodes show that the spark has been jumping from all
> over the center electrode? That would eliminate low ignition voltage as a
> problem.
>
> Does the ignition advancer work?
>
> --
> Message posted via MotorcycleKB.comhttp://www.motorcyclekb.com/Uwe/Forums.aspx/tech/200706/1

i set the float levels when i rebuilt the carbs, holding it horizontal
until the needles just closed with no gasket at 20 mm. maybe i'll try
setting it lower.
i haven't tried holding the spark plug off of the head, just laying it
on the head i get a nice blue spark. i have a brand new battery and
i'm using the electric start.
i haven't disassembled the advance but it seems to be advancing ok.
i've had it up to 40 and there haven't been any flat spots.

From: fweddybear on 15 Jun 2007 23:13
<billybuckshot(a)gmail.com> wrote in message
news:1181949372.794478.70970(a)w5g2000hsg.googlegroups.com...
> On Jun 15, 4:23 pm, MadDog...(a)yahoo.com wrote:
>> On Jun 15, 1:18 pm, billybucks...(a)gmail.com wrote:
>>
>> > I'm having a difficult time getting a friends Honda Cl450 to quit
>> > fouling plugs. I'm familiar with vintage HDs and Brit bikes but this
>> > old Honda is making me tear my hair out. I've cleaned the carbs
>> > thoroughly and rebuilt them with new jets, readjusted the valves,
>> > checked the points, compression (140 psi) but the bike fouls the plugs
>> > (black soot) within 10 minutes of start up. Other than replacing the
>> > carbs completely, i'm out of ideas. Anyone out there familiar with
>> > these old Hondas? Help is greatly appreciated. -Billy
>>
>> Probably an idle though after all this:
>> "Are you sure you've got the proper heat range on those plugs?"
>
>
> To answer everyones questions: i failed to mention that i replaced the
> mixture screws. that didn't help. i also inspected where they seated
> and the was no noticable damage.
> i've also been through about 6 sets of NGK B8ES plugs, that are
> constantly being cleaned in the bead blaster and returned back to the
> rotation. I've also tried hotter B7ES plugs, no difference.

How far out do you have the mixture screws? 1 1/2 turns should be a
good starting point...

Fwed


From: billybuckshot on 16 Jun 2007 00:02
On Jun 15, 10:13 pm, "fweddybear" <fweddyb...(a)cox.net> wrote:
> <billybucks...(a)gmail.com> wrote in message
>
> news:1181949372.794478.70970(a)w5g2000hsg.googlegroups.com...
>
>
>
> > On Jun 15, 4:23 pm, MadDog...(a)yahoo.com wrote:
> >> On Jun 15, 1:18 pm, billybucks...(a)gmail.com wrote:
>
> >> > I'm having a difficult time getting a friends Honda Cl450 to quit
> >> > fouling plugs. I'm familiar with vintage HDs and Brit bikes but this
> >> > old Honda is making me tear my hair out. I've cleaned the carbs
> >> > thoroughly and rebuilt them with new jets, readjusted the valves,
> >> > checked the points, compression (140 psi) but the bike fouls the plugs
> >> > (black soot) within 10 minutes of start up. Other than replacing the
> >> > carbs completely, i'm out of ideas. Anyone out there familiar with
> >> > these old Hondas? Help is greatly appreciated. -Billy
>
> >> Probably an idle though after all this:
> >> "Are you sure you've got the proper heat range on those plugs?"
>
> > To answer everyones questions: i failed to mention that i replaced the
> > mixture screws. that didn't help. i also inspected where they seated
> > and the was no noticable damage.
> > i've also been through about 6 sets of NGK B8ES plugs, that are
> > constantly being cleaned in the bead blaster and returned back to the
> > rotation. I've also tried hotter B7ES plugs, no difference.
>
> How far out do you have the mixture screws? 1 1/2 turns should be a
> good starting point...
>
> Fwed

i had it about 1 1/2 turns out but have had it turned 3/4 to all the
way in and theres not much of a difference. the plugs just take
another minute or two to foul. the carbs have to be completely worn
out but i want to eliminate any possibilities that i've overlooked
something simple before i make this girl spend $200 and up on a set of
decent carbs.

From: Timo Geusch on 16 Jun 2007 02:55
billybuckshot(a)gmail.com writes:

> i had it about 1 1/2 turns out but have had it turned 3/4 to all the
> way in and theres not much of a difference. the plugs just take
> another minute or two to foul. the carbs have to be completely worn
> out but i want to eliminate any possibilities that i've overlooked
> something simple before i make this girl spend $200 and up on a set of
> decent carbs.

So you're saying that adjusting the mixture screw pretty much makes no
difference at all?

--
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Triumph T-Bird chop | K1100LT | CB400/4 BOTAFOF #33 TWA#10
The UKRM FAQ: http://www.ukrm.net/faq/index.html
"Je profite du paysage" - Joe Bar
From: fweddybear on 16 Jun 2007 09:50

<billybuckshot(a)gmail.com> wrote in message
news:1181966566.992622.201820(a)m36g2000hse.googlegroups.com...
> On Jun 15, 10:13 pm, "fweddybear" <fweddyb...(a)cox.net> wrote:
>> <billybucks...(a)gmail.com> wrote in message
>>
>> news:1181949372.794478.70970(a)w5g2000hsg.googlegroups.com...
>>
>>
>>
>> > On Jun 15, 4:23 pm, MadDog...(a)yahoo.com wrote:
>> >> On Jun 15, 1:18 pm, billybucks...(a)gmail.com wrote:
>>
>> >> > I'm having a difficult time getting a friends Honda Cl450 to quit
>> >> > fouling plugs. I'm familiar with vintage HDs and Brit bikes but this
>> >> > old Honda is making me tear my hair out. I've cleaned the carbs
>> >> > thoroughly and rebuilt them with new jets, readjusted the valves,
>> >> > checked the points, compression (140 psi) but the bike fouls the
>> >> > plugs
>> >> > (black soot) within 10 minutes of start up. Other than replacing the
>> >> > carbs completely, i'm out of ideas. Anyone out there familiar with
>> >> > these old Hondas? Help is greatly appreciated. -Billy
>>
>> >> Probably an idle though after all this:
>> >> "Are you sure you've got the proper heat range on those plugs?"
>>
>> > To answer everyones questions: i failed to mention that i replaced the
>> > mixture screws. that didn't help. i also inspected where they seated
>> > and the was no noticable damage.
>> > i've also been through about 6 sets of NGK B8ES plugs, that are
>> > constantly being cleaned in the bead blaster and returned back to the
>> > rotation. I've also tried hotter B7ES plugs, no difference.
>>
>> How far out do you have the mixture screws? 1 1/2 turns should be a
>> good starting point...
>>
>> Fwed
>
> i had it about 1 1/2 turns out but have had it turned 3/4 to all the
> way in and theres not much of a difference. the plugs just take
> another minute or two to foul. the carbs have to be completely worn
> out but i want to eliminate any possibilities that i've overlooked
> something simple before i make this girl spend $200 and up on a set of
> decent carbs.

Does it start right up? If not, you may have an ignition timing
problem....Still not sure what size you are using, but maybe try using
smaller jets. Also, this may be a dumb question, but have you check the air
passages or changed the air filter? You may not be getting enough air. I
am gonna assume the bike is all timed properly too.
I had a similar problem on another bike I have.....I ended up using a
smaller jet, dialed in a different ignition timing, used a hotter plug, and
also readjusted the air/fuel mixture screw. This took me a while to figure
out the proper way..... my main issue was it was hard starting, but it also
fouled plugs.

good luck...

Fwed


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