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salvooch
17th June 2008, 02:50
My sporty takes forever to warm up if not started for a few days or so. I mean about 7 or 8 mins. Then, after warming it up for a while, it'll sputter until I pop it in neutral and open the throttle to clean it out.

Also, it'll 'pop, pop, pop' if I roll off the throttle and cruise in gear (like small backfires). I think I need to re-jet, but not sure.

Any ideas? Just a tune up maybe?

wabiker
17th June 2008, 02:54
What do the Plugs look like ...?
Is your Choke Sticking *On*...?

salvooch
17th June 2008, 03:03
Havn't checked plugs in a while. Choke not sticking on, I have to hold it out as it'll push itself back in otherwise.

Likemlouder
17th June 2008, 05:34
sounds like it is really lean. if you have had the bike awhile and it didn"t do it before.i would clean the carb blow out all the jets good. sometimes they gum up over the winter.you can check and see if it accelerates good with the choke on. then that is where i would start

salvooch
17th June 2008, 09:47
Another thing is when it's warming up, if I roll on the throttle, it'll just die; I guess that does sound like the jets are clogged. It's just never done this before. I guess I'll spend this weekend given it a tune. Thanks to all.

bshadbolt
17th June 2008, 10:45
Slow to warm up usually means too rich, not too lean. Lean motors run hot, rich motors run cold.

It could just be that it is partially flooded as you say this only happens when it hasn't been started for a while - I'm guessing it takes a few cranks to get it started which could easily overfuel it.

If it runs ok otherwise then I wouldn't worry.

Cheers,

Brett

Mattbastard
17th June 2008, 11:28
If by slow to warm up you mean cold blooded, it's lean.

Rich bikes operate very well when cold. Lean bikes spit and sputter when cold.

Folkie
17th June 2008, 11:30
if I roll on the throttle, it'll just dieThat could be an exhaust leak.

salvooch
18th June 2008, 01:36
That could be an exhaust leak.

But it's fine when it's 'warm'.

Based on what you've all said above, I think it's rich. It'll start right up w/ the choke out, but takes forever to get 'warm'. Then, it's like I have to shift to N and roll the throttle back hard, like blowing out the stacks after idling for a while (at least it's like that on a ship anyway!).

That said, I just have to get a tune up and re-jet? I did change pipes a while ago. Either way, she needs a tune (been a while). I hate to take it to the shop ($), so I usually use carb cleaner, clean the k&n, change the plugs, oil and oil filter, and flush out my in-line fuel filter. Any other points you can think of? Guess I can just Google it, too.

Any more pointers are greatly appreciated! This site is great.

wabiker
18th June 2008, 01:59
But it's fine when it's 'warm'.

Based on what you've all said above, I think it's rich. It'll start right up w/ the choke out, but takes forever to get 'warm'. Then, it's like I have to shift to N and roll the throttle back hard, like blowing out the stacks after idling for a while (at least it's like that on a ship anyway!).

That said, I just have to get a tune up and re-jet? I did change pipes a while ago. Either way, she needs a tune (been a while). I hate to take it to the shop ($), so I usually use carb cleaner, clean the k&n, change the plugs, oil and oil filter, and flush out my in-line fuel filter. Any other points you can think of? Guess I can just Google it, too.

Any more pointers are greatly appreciated! This site is great.
Tune-up....Yes, and there aint much you need to do for that.

Rejet...No, at least not until you give it a tune-up. Your looking to open up a whole can of worms if you start messing with the Jetting until you at least LOOKED at the plugs.

In fact, get it out of your head until your POSITIVE you dont have any other issues going on; Exhaust/Intake leaks, Fuel Filter, Air Filter and...PLUGS ;)

This is easy stuff for the DIY'er, a good place to start for the Newbie.

Folkie
18th June 2008, 07:48
It'll start right up w/ the choke out, but takes forever to get 'warm'.Does it start without the enricher out? If it's rich enough to cause these problems, it should.

salvooch
18th June 2008, 09:30
Does it start without the enricher out? If it's rich enough to cause these problems, it should.

When cold, does not start up w/o choke.

Mattbastard
18th June 2008, 11:04
Dude, it's lean

Lean conditions:

need the choke when cold
run better when warm
usually bog the engine when throttle is applied

For some reason people tend to think rich engines bog when you crack the throttle. IMHO, not true. I've taken my bike from really rich to really lean as per my wideband o2 sensor and rich conditions supply really good throttle response, and lean conditions will make the engine bog.

Wanna see what I'm talking about? Go out to your cold bike, turn off the choke and crank open the throttle. I'd bet it dies.

Folkie
18th June 2008, 11:37
When cold, does not start up w/o choke.It can't be very rich then.

salvooch
19th June 2008, 00:39
Matt seems to have nailed it. Guess it's lean. After checking the plugs, cleaning the carb, change the oil/filter, what do you reccomend?

cantolina
19th June 2008, 01:03
My sporty takes forever to warm up if not started for a few days or so. I mean about 7 or 8 mins. Then, after warming it up for a while, it'll sputter until I pop it in neutral and open the throttle to clean it out.

Lean...not ridiculously so, but a bit....

Also, it'll 'pop, pop, pop' if I roll off the throttle and cruise in gear (like small backfires). I think I need to re-jet, but not sure.

Any ideas? Just a tune up maybe?

Different issue, different cause....this is typically an exhaust leak....or drag pipes..;)

Dude, it's lean

Lean conditions:

need the choke when cold
run better when warm
usually bog the engine when throttle is applied

The first two things mentioned here are not lean conditions...they are actually quite normal...see below for the third...

For some reason people tend to think rich engines bog when you crack the throttle. IMHO, not true. I've taken my bike from really rich to really lean as per my wideband o2 sensor and rich conditions supply really good throttle response, and lean conditions will make the engine bog.

Wanna see what I'm talking about? Go out to your cold bike, turn off the choke and crank open the throttle. I'd bet it dies.

"Bogging" is a very specific and technical term...:laugh:laugh

Typically, when I am addressing "bogging", its in response to a wide-open throttle crack and a lack of anticipated response after a second or so....NOT dying altogether....and it follows that when there is a "bogging" issue as I describe here, it CAN very well indicate a rich condition in the main jet (I'm talking stock CV carbs here) I don't typically even equate "bogging" with the pilot jet at all...

I guess what I'm trying to say is that stalling is NOT bogging...bogging is a refusal of the engine to appropriately respond to a given throttle position...

Matt seems to have nailed it. Guess it's lean. After checking the plugs, cleaning the carb, change the oil/filter, what do you reccomend?

Well, if you checked the plugs, what did they look like?

In the end, after a good carb cleaning and inspection of vacuum hose/petcock diaphragm, etc., my next thought would be to tune the pilot circuit...probably just a mixture tweak, rather than a rejet.....

Mattbastard
19th June 2008, 02:23
I've had a perfectly tuned Sportster, tuned with a wideband o2 sensor, spit out WHITE plugs for miles and miles. The reason they come out like that all the time is because they are some of the hottest plugs you can put in a bike. The heat just keeps burning off crap that builds up. I've tried plug chops before, and I just bought a wideband eliminate the guesswork. Unless my sporty is just some anomaly, the only time I get dark plugs is by bombing around town under 30. My wideband says it's in the mid 12's : 1 at that point. On the highway, it cruises at 14, and accelerates at 13:1.

I started using the V-rod plugs. Sparks just the same, just less ceramic around the electrode to promote dieseling and unnecessary heat.

Besides, whens the last time you've heard of a stage 1 sporty, without any carb work, being rich????