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RE: Manual Choke

deadman — Thu, 10 Jul 2008 23:09:45 GMT

jerseyjim (7/10/2008)

DEADMAN:

"...blow it out the breather...." Yep. Anytime the bike is not used longer than 2 months, I've learned to remove the air cleaner, disconnect the breather hose and put it in a funnel to a small dish, bottle or whatever. First time it happened, I was totally unaware and it make quite a bit of mess on the floor. Now I know.

Local indi shop I use says it's probably the ball bearing against the spring getting worn in the oil pump. It permits a very small leak into the crankcase....and two months of this.......

This never happened until 5 years ago (after I retired and started the winter RV trips) because BEFORE I retired, during the winter when there was snow, ice, or just too darn cold, I started and ran the motor every Sunday afternoon...got it up to "operating temp" then shut it down (until next week).

Enjoying your 112 degrees?

Ahh, blow it out your breather! lol

Yeah, that little ball-n-spring is the check valve that's supposed to keep oil from draining back into the crankcase. After many moons the ball and seat get beat up, gummed up, whatnot.

Right now it's 72 and raining...raining...what's that wet stuff?

This time of year I don't ride too much. When I do, I/we get an early start and head north, and come home late. Of course it's still 85-95 at 7am and midnite, but riding in the valley at 112-115 is pure misery. Go ahead, ask me how well I know...

RE: Manual Choke

jerseyjim — Thu, 10 Jul 2008 02:53:07 GMT

DEADMAN:

Local indi shop I use says it's probably the ball bearing against the spring getting worn in the oil pump. It permits a very small leak into the crankcase....and two months of this.......

Enjoying your 112 degrees?

RE: Manual Choke

deadman — Thu, 10 Jul 2008 01:36:50 GMT

EDIT: Rootie, good point on the molybdenum disulfide. I'm on a mission now to see if the dino and synth oils spec'd for wet clutches have it...

I've done a ton of dealer turbo work for 2 Mitsu dealers, and I've never heard of a specific turbo-use gas additive. Also, the turbo cars get the same oil as non-turbos(whatever min-spec oil the dealers could get cheapest).

That doesn't mean it's not out there being marketed, but then so is the "intake tornado"!

As far as cleaners go, most of it is just marketing. The only FI cleaner I'll use or recommend is Chevron Techron. Most all current injectors are self-cleaning, rotating-plate style, and will never need cleaning anyway...but it also cleans up the fuel system and everything else. But then, a little water is a great top-engine cleaner too.

If you've got seriously carboned up valves or chamber, GM's Top Engine Cleaner rocks.

Jimmy: As far as the lay-up use of MMO goes, anything's better than nothing in keeping cyl wall rust at bay for long layups in damp conditions. The reason you don't see any smoke, etc. at startup is because by the time it's started, it's long since drained past the rings and into the crankcase-the same reason your application is less harmful than running it through the engine and the combustion process continually. Just keep the amount small...that dry-sump crankcase doesn't take much to fill up enough to pop seals and/or blow it out the breather before the oil pump can scavenge it away.(shovels were awful for this, but evo's still do.)

RE: Manual Choke

Rootie — Tue, 08 Jul 2008 12:47:38 GMT

Quote - Charon: "I was under the impression that synthetic oil isn't more "slippery" than mineral oil, but that it has a higher film strength. I thought the problem with clutches was in energy-conserving additives, not in the base stock of the oil. I stand ready to be corrected, if I am mistaken."

One of the most common energy conserving additives is molybdenum disulfide. Ultra slippery stuff and I can see why you wouldn't want that in your oil if you have a wet clutch.

Cars that are turbo charged require a motor oil that meets certain specifications. I was told that one of the reasons is it leaves a better film on moving parts for cold starting or kicking in the turbo before the motor oil reaches optimum flowing temp. I was also told there was a specific gas additive for turbo engines also. I wouldn't know firsthand - I've never owned a turbo charged vehicle. The closest I ever came was when I left the cover off the air cleaner!

Most gas additives not only claim to lubricate the upper cylinder but also keep valves clean. Can an additive do both - or are we being fed lies?

RE: Manual Choke

jerseyjim — Tue, 08 Jul 2008 04:21:33 GMT

Gee...you guys knocking a BIG favorite of mine....Marvel Mystery Oil.

When leaving the house (in my RV) for a winter cross country trip to, say, Arizona and back...knowing the bike will sit for at least 4 months...part of my "ritual" is to remove the spark plugs and shoot 5 or 6 squirts of MMO into each cylinder...then spin the motor two or three seconds.

Hoping this will stop any rust or other bad stuff during the cold, damp winter months, I've NEVER noticed any ill effects (like smoking upon first start-up) or anything else. Oil consumption is "normal", like 1/2 qt between the 3,000 miles oil changes.

'92 H-D dresser...42,000 miles and runs perfectly. I've done this MMO thing 5 times.

What can I say?

RE: Manual Choke

deadman — Mon, 07 Jul 2008 20:20:53 GMT

Charon (7/7/2008)

If I were going to add any sort of "upper cylinder lube" to my gas, I'd probably just use 2-stroke oil. That stuff is supposed to go through combustion chambers. But I sure wouldn't use much of it. For information, the last of the 350 Yamaha two-strokers imported into the US (except California) had catalytic converters on them. Presumably the two-stroke oil didn't destroy them, or I doubt the EPA would have allowed them to be imported.

I was under the impression that synthetic oil isn't more "slippery" than mineral oil, but that it has a higher film strength. I thought the problem with clutches was in energy-conserving additives, not in the base stock of the oil. I stand ready to be corrected, if I am mistaken.

IMHO, it's the film strength that makes it slipperier(?) and clingier(??). My understanding is that the dino oil molecules are easier to seperate and squish out from the area under pressure, whereas the synth molecules bond more strongly together. In a clutch, it'll maintain a thicker layer between the clutch plates, leading to more slip.

I once had an engineer at Richmond Gear recommend a synth diff lube for a noisy ring and pinion set. His explanation was that the synth molecules are physically larger, and provide more of a cushion between the gear teeth, cutting down the noise.(rear whine is really the teeth contacting the tooth faces)

Was it the film, the molecular size, or something else? I'm not an oils engineer, I don't know for certain.

But it worked!

RE: Manual Choke

deadman — Mon, 07 Jul 2008 20:08:31 GMT

Doesn't 99% of it burn off when the fuel ignites?

If you mean an additive: Whatever is still atomized, should burn off-(but then it's not aiding in coating anything anyway!), but it'll soak in around the top ring and thoroughly coat the valves. Neither of these are subject to full combustion pressure and temperature spike, and you'll find plenty of carbon left there. Eventually it'll carbon up the chamber like a bad ring, too.

If you mean the synthetic: Not much. As the piston rises, oil(synth or dino) from the oil ring coats the wall. On the downstroke, the top and second rings scrape it back off-this adds to any spritz from the rings and helps coat the skirts . The synth clings in the oil ring and to the piston skirt better, so the walls/skirts get lube sooner.

Easy test: Got a car that goes knocka-knocka on cold start?(piston slap) Change to synth...nite and day difference.

RE: Manual Choke

Charon — Mon, 07 Jul 2008 14:53:43 GMT

RE: Manual Choke

Newbie — Mon, 07 Jul 2008 11:36:13 GMT

I think it was the dealer that told me not to run with synthetic as it would effect the workings of the clutch. The clutch needed the less slippery stuff.

RE: Manual Choke

Rootie — Mon, 07 Jul 2008 08:45:51 GMT

[quote]deadman (7/6/2008)

I'll second that. Unless it's a 2 stroke, don't put anything in your gas other that the occasional octane booster or FI cleaner. The net effect of diluted oil on cylinder lube, is squat. It will however do a bang-up job at caking the valve heads and ring landswith crud!

If dry cylinder walls really concerns you, run synthetic. It clings better to the walls and skirts.[/quote]

Doesn't 99% of it burn off when the fuel ignites?

RE: Manual Choke

Newbie — Mon, 07 Jul 2008 07:57:57 GMT

Since I am a simple guy I did the simple things...just tightened the thing around the choke and stopped trying to drive with the choke full on and it has made a world of difference. Ran around both Saturday and Sunday and it only stopped the one time but I might have still had it closer to 3/4 open rather than 1/2. I love the bike and the fact that it uses regular gas but hate the manual choke. Might have to go to FI next time.

RE: Manual Choke

deadman — Sun, 06 Jul 2008 23:12:04 GMT

If dry cylinder walls really concerns you, run synthetic. It clings better to the walls and skirts.

RE: Manual Choke

Gfurlo — Sat, 05 Jul 2008 14:46:28 GMT

[b]Rootie (7/5/2008
What to do? Well, aside from never starting your bike, you could add something to your gas tank to provide some lubrication from the gas itself. I have talked to a number of mechanics who recommend putting a small amount of Marvel Mystery Oil or even regular motor oil in with your gas.

Do not do this with an engine that has a catalytic converter, it is amazing how little oil it takes to kill one.

RE: Manual Choke

jerseyjim — Sat, 05 Jul 2008 11:41:04 GMT

My H-D has a Mikuni....and the EPA specs had my motor spitting and sputtering for the first 10 miles...and the plugs were just about white. Burned out after 3-4000 miles.

Re-jetted...end of problem.

Also...an "enricher" (as oppsed somehow to a "choke")...and it does tend to pull itself in, I just hold it out until the motor can hold it's own idle...usually about 20-30 seconds, the I ride off (into the sunset or to work...whichever comes first).

Be advised....any dealer will NOT re-jet...they are forbidden to by law, so will tell you anything (like "needs a tune-up). Aftermarket shops, however, don't seem to mind doing things like this...or you can do it yourself.

RE: Manual Choke

Rootie — Sat, 05 Jul 2008 11:25:43 GMT

rneilsen brings up a good point about full choke and flooding your engine with gas. After your bike has sat for a while any oil that was on the cylinder walls and pistons will drip down due to gravity. The longer the bike sits, the less oil residue will be on the metal parts. So when you start your engine you are starting up with very little oil in the combustion chamber. Then, with the choke on full, you are flooding your engine with gasoline and washing off what little oil remained.

It takes a little while for cold engine oil to start flowing efficiently so these "dry" starts probably cause more engine wear at startup than running your bike all day. Plus, it is important not to leave your bike on choke longer than the minimum time it takes to get it running smoothly.

What to do? Well, aside from never starting your bike, you could add something to your gas tank to provide some lubrication from the gas itself. I have talked to a number of mechanics who recommend putting a small amount of Marvel Mystery Oil or even regular motor oil in with your gas.

RE: Manual Choke

Newbie — Sat, 05 Jul 2008 07:21:29 GMT

Thanks guys, I will try what you suggested.

RE: Manual Choke

deadman — Fri, 04 Jul 2008 22:11:55 GMT

It's carbureted, with a Mikuni CV. That carb actually uses an enrichener, not a choke...but their effect and use is essentially the same.

Tighten the knurled nut under the "choke" knob to stop it from adjusting itself, and don't obsess over exactly how long to run it...Every bike has a different choke use strategy, and that bike will change it's needs with atmospheric changes.

Once you're moving, the choke's off(it's fuel metering passages are inactive just above idle anyway). I typically like a bike to able to idle without the choke after 5 munites or so. EPA-friendly factory lean settings tend to lead to longer choke use needs. The only actual fix is to tune the carb(jet kit, mixture adjustments, etc.) and a dealer will not do this.

Adjusting the idle speed higher is just a bandaid for a lean mixture, and when it does warm up it'll idle way too high.

RE: Manual Choke

rnielsen — Fri, 04 Jul 2008 17:10:14 GMT

Generally you should move the choke to a partial position when you start riding the bike. Full choke is used mostly for starting.

If the choke knob moves toward closed on its own, you may find a plastic collar beneath the knob that can be tightened to put more friction on the choke control cable. That way the choke will stay in whatever position you choose. Be careful, it's plastic and easily broken.

Full choke is usually to be avoided when riding as it often floods the engine and the extra gas dilutes the oil in the crankcase.

I'm not sure if your bike is carbureted or fuel injected, but with a choke knob I suspect it's carbureted.

When I had carbureted bikes I'd use full choke to start it, then back off about half way while I put on my helmet and gloves. Then, the choke was shut off and I took it easy for a couple of blocks until the engine would run smoothly.

Hope that helps a bit.

Ray Nielsen, in Minneapolis and going for a breakfast ride tomorrow.

Manual Choke

Newbie — Fri, 04 Jul 2008 13:42:37 GMT

I have an '08 Honda VTX1300 but it keeps stalling. I know that the problem has to do with my use of the manual choke as the gas is good and the idle has been reset by the dealer. When I start off I will run it with the choke full open but because of the rumble it will slowly shut it back off. After running for about 10 minutes it will be fine and not stall, it is just that first darn 10 minutes. The dealer had said that if I run it too long then when you slow down the carb gets flooded and it will stall and this is exactly what seems to be happening. Should I boost up the idle a bit more? Or should I run it with less choke for a shorter timeframe since it is warmer out?

Thanks for any help...