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-   -   Just bought a Sportster, and am beginning to have problems (https://www.hdforums.com/forum/sportster-models/674079-just-bought-a-sportster-and-am-beginning-to-have-problems.html)

1200Cdriver 08-06-2011 09:35 AM

GTK, you can vouch for the fact this is especially true on a real hot day after a brief shutdown and then restart.

NickD 08-06-2011 10:38 AM

Like mentioned upboard when these motors stop on the compression stroke you need a good battery to overcome it. There's a chance (with only 235 miles) your battery is original and, like the rest of the bike, has been neglected. I don't mean abused, but not being ridden is just as bad as beating it with a hammer. Dollars to donuts your battery has a sulfide issue (the acid has eaten away too much of the lead plates.) Get a new battery.

As for the oil in your carburetor throat, you can thank the MOCO for that. Starting with the Evo they finally managed to make a fairly oil tight motor. Except for one weak spot - the oil return system from the heads. At cruising RPM the oil return system is overcome by pressure and/or volume. So rather than make a multi-million dollar redesign they slapped a band-aid on it. The took this oil called "blow-by" and routed it from the heads directly into the carburetor to be burned during combustion. Blow-by is actually three fluids. Air, oil and due to condensation, a certain amount of water.

On a frequently ridden bike this blow-by never gets a chance to harden but on a bike that sits for years, well, you can just imagine. And while this blow-by doesn't travel through the fuel supply passages if left to sit it can gum up the tiny orifices. The fix is to route the two hoses from the heads, not to the back of air cleaner, but to a T-fitting and then to a single hose that runs down under the bike to drain. The MOCO would have done that, but of course the EPA won't let that fly. If you're green you can affix a small canister to the drain hose that you'll have to empty out from time to time.

An ancillary problem you'll have, due to the bike not being ridden, is whatever fuel was left in the carburetor evaporates and leaves a residue behind that becomes like a shellac and that really screws up the works. So I'll offer you need to rebuild the carburetor. There are kits for this that cost about $30 - $40. And it's not a difficult job. Besides replacing the rubber parts, ie, gaskets, accelerator pump bellows and whatnot, a one gallon can of carburetor cleaner from the auto parts store (comes with a parts basket) will clear all that crap out. If you lack an air compressor at least use one of those cans of compressed air (like for electronics and computers) and blow out all the small fuel passages prior to re-assembly.

So, my suggestion is to buy a new battery, rebuild your carburetor, and do the blow-by mod. Also, if it was me, I'd add an additional external fuel filter. If the bike sat without the fuel tank being totally full, who knows what's growing in there.

For the carburetor rebuild there are some vids on Youtube, here's one:
http://www.youtube.com/watch?v=m0sZ32EVUYY

:)

WRAITH 08-06-2011 11:43 AM

I have 100,000+ miles on my 06 XL1200C. The problems you have mentioned are common to all pre 06 models. I chewed up 3 starter clutches before I found how to deal with the "kick-back" problem. It is caused by, one of the pistons being at top dead center when you hit the starter button. The cylinder is already compressed and fires against the starter causing the "bang" and brief hesitation. There are a number of easy ways to deal with the problem. The simplest is, "tap" the start button rapidly once before fully starting the engine. The "tap" allows the cylinder to fire with out putting reverse pressure on the starter. The other solutions are more expensive but don't require any pre-start thinking. Install electronic decompression valves. These are found on all TC engines. Use an aftermarket ignition module that will allow you to modify the ignition timing ( stock timing can not be modified). The best way to deal with the "blow-by" oil is not to over fill the oil tank. Keep the oil level at half or below on the dip stick. Note: Always check the oil level when the engine is Hot and the bike is on the side stand.

XTsHOG 08-06-2011 01:26 PM

Grrreat info NickD!!
Hey Wraith do u tap it all the time? Almost sounds like a good practice.

1200Cdriver 08-06-2011 03:34 PM

Actually the compression would rapidly leak off if the engine stopped at TDC on compression, there would be no pressure left in the cylinder after a few seconds. It is rare for an engine to stop at TDC on the compression stroke. If you've ever seen a flywheel from a V8, there will be four places around the flywheel where the starter teeth are worn more than the others and that is the four places the engine normally stops between compression strokes. If our starters directly engaged the flywheel there would be two of those places with one being much more promenent than the other.

Jackie Paper 08-06-2011 04:11 PM

I do not think it's a problem. If you battery has been charged and load tested you know it's good. You know the wires are tight. (mine get loose about once a year since my wires are cramped for space and a softail battery can move around a little) Quite often but not ever time mine does that slight hesitation till it gets moving. I think its just the v-twin engine doing it when the last time it stopped it left one piston coming up on the compression stroke. Since that one can not help with the cranking you get that slight hesitation. Mine has always done it and it has 40K one it. Do not worry about the oil. They all do it. If your oil on the stick is at full when hot you are fine. If you fill compelled to lower it half way between full and add fine but in about 500 more miles the engine will have less blow by then when new and the oil there will be much less anyway. my opinion is even 3-6 oz less oil is a rather large precent of the cooling oil since there is but a few quarts in these engines. This is considered a dry sump engine and the oil at full is not what causes that. I run mine when hot at full to the top mark. Just wipe the drool from its chin once in a while. Additives like Seafoam serve no purpose in these engines except coak up the engine which can break loose and scar up the cylinders

straightexhaust 08-06-2011 04:24 PM

Do I need a breather kit? My only concern would be the carbon buildup from burning the small amount of oil and if so does anyone have a breather kit that they recommend. I have come across several that route them together through a steel line and banjo bolts, then you hook up a hose to them but that style claims to not work with the stock air cleaner which I would rather keep to keep the costs down.

Jackie Paper 08-06-2011 05:23 PM

That small amount of oil that is overwhelming the breather screen and baffle system in the head and dropping out of the air flow pretty much never gets much further then what you see in your photo. Actual if you put one of those open box filter on the oil you see drips out back side of filter and down on cam covers. I had a 1100 Yamaha V-Star that had a drain tube about 4" long attached to the bottom side of the air filter box at a small cavity. It had a rubber plug in the end of it for draining. One note when you do not run your bike like for a month or two like in winter all the oil up in the tubes and such will drain down to the lowest point and make it look like a lot more. Since mine has the silly SE filter with no back plate if it sits a while my first drive will drip a couple drops. After that it just keeps the filter wet, sort of self oiling filter.

John Hyatt 08-06-2011 06:40 PM

Dammmm nice Ride Nick !!!!!

J.

NickD 08-06-2011 09:46 PM

Thanks!

>>Actually the compression would rapidly leak off if the engine stopped at TDC on compression, there would be no pressure left in the cylinder after a few seconds.<<

I'd say they mostly stop at the beginning of the compression stroke not TDC. So when you hit the starter both valves are closed (at least in one cylinder) and the battery/starter must overcome that first compression stroke. It's why big motors have compression releases.

:)


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