Grrr Carbs again.....

[KEITH KRAUSE]

Keith,

Thanks for the kind words. In case you missed the thread, here are the new canine members of the Nardy household, Koa and Norton:



Now back to Dan's carb issues................

Thanks,
Joe

Oh my goodness!! If cute looks could kill I'd be dead.
Enjoy those little buggers!
Again, so happy for Layla!!:-D

[KEITH KRAUSE]

So a much smaller main with pretty much the same everything else... maybe that's the issue. I hope to be changing to the Jardines soon anyway so I guess I might worry about it again then...

Sorry Salty about the subject detour. Hard to compete against those pups.
Kinda wondering if you really do have the correct carbs on there or if they're only "close". Not sure what else to do 'til you can make those high speed tests.
What bothers me is the backfiring, if I'm correctly understanding it as a true "bang" backfire. Usually, a backfire is from unburned fuel collecting inside the head and header and at a saturation point you get one big explosion. Unburned fuel can accumulate because of a weak/problem spark and/or rich mixture. If you say the jetting is close to stock if not identical, that leads me back to a spark quality/timing problem.
I've seen quite a few bikes with rich jetting and they didn't backfire.
I'd be sure to inspect the spark quality and timing first. If you have the tester and info to check the ignitor, I'd do that too. If it passes all tests and you know the connections are good and plugs are good, then I'd focus on the carbs.

[salty_monk]

hehe you're not wrong! They're too cute.

The carbs are as listed as a stock set for my bike. The K&N is the only real difference & running a GS1000 exhaust instead of a 1000G exhaust (only difference is a couple degrees in the bend as far as I know).

Took the bike out again today, I'm running sea foam in the gas at the moment (I didn't have it in there the other day. Trying to clean the valves up, they looked a bit sooty through the intake). Anyway, today it seems much better & there is no real other difference today, it's warmer out though than the other day but that's it.

I don't think it can be ignition, the ignitor set seems ok, the coils are new dyna greens & plugs & leads are pretty new too.

I wonder if my vacuum tube could be collapsing & shutting off fuel... It's due for replacement anyway so I'll be doing that soon & cleaning the K&N.

Regardless this is now the best the bike has run since I've had it so it's all a plus.

Dan

[Joe Nardy]

hehe you're not wrong! They're too cute.

The carbs are as listed as a stock set for my bike. The K&N is the only real difference & running a GS1000 exhaust instead of a 1000G exhaust (only difference is a couple degrees in the bend as far as I know).

Took the bike out again today, I'm running sea foam in the gas at the moment (I didn't have it in there the other day. Trying to clean the valves up, they looked a bit sooty through the intake). Anyway, today it seems much better & there is no real other difference today, it's warmer out though than the other day but that's it.

I don't think it can be ignition, the ignitor set seems ok, the coils are new dyna greens & plugs & leads are pretty new too.

I wonder if my vacuum tube could be collapsing & shutting off fuel... It's due for replacement anyway so I'll be doing that soon & cleaning the K&N.

Regardless this is now the best the bike has run since I've had it so it's all a plus.

Dan

Sounds good Dan! Hopefully it will be okay from here on out..........

Thanks,
Joe

[salty_monk]

It'll certainly make it to Yosemite again... how about you??

[Joe Nardy]

It'll certainly make it to Yosemite again... how about you??

Dan,

I'm not sure yet. I have to see how finances work out. It's a great trip but rather costly when factoring in the cost of renting a bike.

Thanks,
Joe

[salty_monk]

Joe,

How about borrowing or even buying one & then re-selling it? I'm sure one of us can help figure something out.....

I can pick up another one if you want to do the LA ride....

Going to fit those new Jardine 4:2 cans before I do any more messing with the bike... Worse case I'll use this new V&H & get pods & a dynojet kit.....

Dan

[salty_monk]

Well back to the carbs....

Went on a 70 odd mile run today, mostly freeway. The bike ran well but opening the throttle hard would cause the bike to miss & didn't pull very hard.
This seemed to improve when it was cold after work but the situation is a little different.

Tonight Took one of the sidecovers off & went out & did the stop sign grand prix This stopped the miss but the bike felt restricted at pretty much all throttle positions apart from low throttle, sort of held back so I guess it was lean.

I then put some tape over one end of the filter, replaced the cover & went out, it was very good on the needle not great on WOT (but seemed better) . It banged a couple of times when shutting off the throttle quickly.

I then removed the filter & put a full line of tape down the snorkel side of the filter in an attempt to make it much richer.
The miss/banging & popping came back when opening the throttle & also when shutting off but WOT seemed to pull even harder.

From this my initial diagnosis:

WOT is lean - increase Main Jet
Needles probably about right, seem restricted at the higher end when Main Jet comes into play so should be sorted by the above.

Bike is going rich when I shut off the throttle causing the banging, this would make sense as I'm currently running pilot screws at 2.75 turns out. I think half a turn or so in would maybe sort this out.

I've left the line of tape on & will test further tomorrow if I get chance.

Anyone else got further thoughts... I'm definitely leaning towards running the V&H with pods & a DJ kit at least we can predict the setup on that

[salty_monk]

Taped up the air filter a bit more tonight, running good though restricted top end (won't pull past 7k rpm).

I imagine the restriction doesn't give a linear effect, it must cut a larger proportion of air as rpm's increase I would think - does that make sense?

Question is now, do I put some 117.5's in, put some 120's in or wait till I've made a decision on my exhaust & set at it then.

What main jet would be recommended with K&N inbox & the V&H if I go that route.... Kent uses a 120 on his 1100, stock is the same as mine at 115 so I guess the same might apply... if I'm lucky