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Engine Mechanical TopicsDiscussion for motor builds, cams, head work, stripped bolts and other engine related issues. The good and the bad. If it goes round and around or up and down, post it here.
Long time reader first time poster.
I have a Harley Sportster Iron 883.
It did have a 1st stage on it (Screamin' Eagle filter and V&H Short Shots) and I *think* it's been tuned with the supertuner (I have the orange box as part of the sale with the bike) and I can see some reference to it on a previous receipt.
However, the V&H SS has been removed (live in an apartment complex and i'll be waking everyone up), so it now only has the filter on it.
The throttle was sticking open a fraction and it felt like it was running a little lumpy. I investigated taking off and cleaning parts right down to the throttle body intake using throttle body cleaner - images attached.
There seemed to be a fair amount of oily deposits which were actually fouling the operation of the butterfly valve by a few mm.
I think as a result of putting the stock exhaust back and not re-tuning it back to stock I'm assuming the engine is running rich.
I think the next step is to buy the supertuner cables from Harley Heaven and re-tune back to standard.
Two questions that i'd really appreciate some advice on:
Can advise if my suspicions are correct regarding the engine running rich based on the images and history?
Additionally, I've looked at a couple of Youtube tutorials for how to program the bike with Stage 1 settings - there appers to be pre-set values to choose from for the most common modifcaitons. I didn't see an option within the software to return the bike back to stock settings. Can anyone please advise if this is possible?
The exhaust change may be your problem as you said. Dirty, oily throttle body for sure. I know you cleaned it, be sure you clean up inside the IAC hole at top of the throttle;
Put in new plugs. Fresh gas, run maybe 50 / 100 miles. Report how it runs. Pull the plugs and post a picture.
I don't know much about the Super Tuner. Someone will kick in here about that.
Oily deposits in the throttle body is more likely caused by the breather system.
The injectors are after that point. There should be no petrol there to gum up the butterfly.
Check spark plugs for rich running.
Give it a good clean and see if it returns. Check oil level for overfill. Most folk run about mid point for oil on the dipstick. Check when engine is hot after a ride.
However, the V&H SS has been removed (live in an apartment complex and I'll be waking everyone up), so it now only has the filter on it.
But what, stock? Might as well put it all back to stock including the tune.
Last edited by Andy from Sandy; Jul 8, 2021 at 05:57 AM.
If you install the stock exhaust just flash it with the stage 1 map from the tuner. You will be fine. Regarding the oil, make sure it's not overfull and clean it up. Also clean the temp sensor bulb that hangs down into the throttle body. Then monitor and see if it's excessive.
And for gawd sakes, get an external breather system. It has no business being routed back in the intake in the first place. This is one of the first things remedied by anyone with an ounce of sense. Screw the epa.
From the looks of that intake, I'd sure hate to see what your combustion chamber looks like.
While stuff on the outside of the throttle blade is likely caused but head breathers, you can get the crud on the inside even with external breathers especially if you have the slightest bit of reversion and the slightest bit of oil leaking past the guides. The reversion blows the stuff leaking past the valves back into the intake port. Once there it simply builds up over time as there isn't anything to wash it off, due to the fuel being injected right at the valve. Carbs don't have this problem or at least as much since fuel come in at the beginning of the intake manifold. I've taken apart EFI motors with lots of miles and the intake manifold were pretty crudded up.
Really appreciate the comments and insightful advice.
So since inspecting and sharing the pictures I've now done the following:
Cleaned up intake, IAC, Air filter and surrounding components
Replaced Oil
Replaced Transmission Oil
Removed, cleaned and re-torqued spark plugs (looked relatively normal, slightly black but nothing major)
Re-installed V&H SS exhaust with new gaskets and retaining clips
It does run significantly better, no more smell of petrol when stopping at the lights etc.
I'm not sure it's sustainable, living in our apartment block so as a back up I'm going to re-flash it to Stage One anyway (to be sure, and to at least know the mapping starting point).
I'll re-fit the standard pipes if I get any noise complaints with new gaskets and retaining clips.
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Is my bike incorrectly tuned?
