Topic: Seafoam down spark plug holes?

[Scott S]

 I've been doing a lot of searching and can't quite find this exact scenario/question.

 I have a bike that's been running really rich and has some carbon build up on the piston tops. I'll be addressing the rich running and giving it a full tune-up, but I was wondering if I could squirt a little SeaFoam down the spark plug holes and let it sit for a bit to loosen the carbon. Then, fire it up and run it for a bit before changing the oil.

 Just a one time thing to try to help loosen and remove some of the carbon without doing a tear down. It's not horrible carbon, but could definitely stand to be cleaned out if possible.

[flybox1]

before my rebuild, i soaked carbon coated pistons in seafoam.
It did loosen it up but they were better after a scrubbing.
IIWM, i'd just get it tuned right, (correct AF mixture across the throttle range) and then run the snot out of it.

[calj737]

If you do use SeaFoam, they make a "Deep Creep" formula that will work better. But, I doubt it would de-coke your engine in the way you're thinking. There are other methods for doing this, a search across Google or YouTube provides pretty good methods and steps.

[Duanob]

Berryman's makes a pretty good carbon remover. Pretty much dissolved right off. And like Fly says run the snot out of it that's what will keep the cylinder clean.

[seanbarney41]

Don't hydro-lock your engine please

[goldarrow]

I say save that money from buying seafoam and invest in brass hardware for the carbs

[chewbacca5000]

Nothing works when it is freezing cold out.  I normally fill up with 50/50 atf/acetone and let it sit for 4 to 6 weeks to break up the carbon and varnish.  Take all plugs out kick it over to get mix out then put plugs in and run.

[faux fiddy]

then run the snot out of it.

+1 on the Italian tune-up. Seems to be working for me.

[Don R]

X2 on the tune it and ride it. A proper dose in the fuel will not hurt it. I've soaked arb parts in seafoam with little result. I guess that's not what it was made for.

[Deltarider]

... and invest in brass hardware for the carbs

It's not the first time you give this 'advice'. I wonder what makes you so sure. My experience is the contrary: brass parts rarely wear if at all. No wonder if you realise how little gasoline pass these parts on a 500cc engine with no less than four carburetors. In this forum you see often people have returned to their stock brass parts after disappointing results with for instance Keyster parts. 

[Airbusboy]

I bought a '83 CB1000C once that a PO had a 'friend' adjust the valves. Well, he didn't know what he was doing and both #1 exhaust valves were shimmed WAY too thick and they didn't close. Though he was lucky enough NOT to burn the valves, LOTS of carbon built up, the valves wouldn't close and compression went south. He sold it to me thinking the #1 cylinder was toast.  The advice from the guys at the DOHC club was to properly shim the valves, put a HEAVY dose of Seafoam in the fuel and then 'Run-it-like-you-stole-it!', and it worked! The carbon cleared out and compression came back to near normal so I'm a BIG fan of Seafoam!

[evanphi]

then run the snot out of it.

+1 on the Italian tune-up. Seems to be working for me.

Me too. First ride of the spring is a dose of seafoam and a heavy-right-hand ride.

[ekpent]

... and invest in brass hardware for the carbs

It's not the first time you give this 'advice'. I wonder what makes you so sure. My experience is the contrary: brass parts rarely wear if at all. No wonder if you realise how little gasoline pass these parts on a 500cc engine with no less than four carburetors. In this forum you see often people have returned to their stock brass parts after disappointing results with for instance Keyster parts. 

Think he may have been alluding to the fact that maybe some carb tuning, jet swapping may be in order to help alleviate the rich running condition.

[goldarrow]

... and invest in brass hardware for the carbs

It's not the first time you give this 'advice'. I wonder what makes you so sure. My experience is the contrary: brass parts rarely wear if at all. No wonder if you realise how little gasoline pass these parts on a 500cc engine with no less than four carburetors. In this forum you see often people have returned to their stock brass parts after disappointing results with for instance Keyster parts.

Not suggesting to replace with keyster kits.  Just new different sets.  All of my bikes run on using stock brass hardware set by the way. 

[Scott S]

 I'm not opposed to new brass....IF I thought it would help and IF it was available.
 Tried to find 550F emulsion tubes lately?

 Plus, the parts are all genuine Keihin except for the float valves and the bike has less than 7k miles on it. Not saying it isn't possible something is worn but I find it hard to fathom.
 I WILL check fuel level with a clear tube since the new float valves might not work at the 22mm height.

 Full tune up is on the way and I'll do Seafoam in the gas and a hard right hand when done.

[KiefRichards]

You could also make a quick water injection rig with a small bottle and lines to the sync ports on carb.
Turn it on under full load, it'll knock that carbon right off!
Low volume on the water, though! 

The tip from a mig welder shoved into the water feed lines works as a good restrictor.

[Feets007]

Yamaha royal stars have a car on problem. I have, and Yamaha pours a bottle of Techtron in it with a full tank of fuel ride it out then oil change.

[Builder]

I used to use water on high carbon buildup. Take off the air filter box. Run the bike at a high idle with the throttle and spray water into the carb. Just keep it running. The carbon will steam off and go out the exhaust.