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Dirty carbs or ??

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SECTION8

Dirty carbs or ??

Ok so another newbie question but ive found asking here is the fastest and most accurate way of finding quality info out so here is another,
My 81 750k is my very first bike so i have nothing to compare to. Ive noticed that my acceleration seems to be sluggish around 2500-5500 in 1st,2nd gear.. Ill give it the throttle and hear the motor and Rpm's increase but the acceleration just doesnt seem to be what I think it should? Understanding its over 30 years old and only a 750 yada yada i got it- Is it dirty carbs/something else or normal for these?
As always THANK YOU to all who respond!

P.s. If it is carbs, is there any method of cleaning that doesn involve total restoration and a migraine!

Army Combat Vet (Iraq 2005-2006) 4th Infantry Div.
1981 Honda CB750k

Lucky 1

Re: Dirty carbs or ??

Motorcycle carbs are not like a car. You do not need to completely strip them and it can lead to problems if you do not know anything.
One of the most critical parts in a motorcycle carb is the float needle.
Just replace those every two years or so.

But .. the idle jets can be clogged up . Especially if it has been sitting around.

It could be something other than the carbs also like the timing and the points and condensers.

Always do carbs very LAST in a tune up process.

On a Roadstar Adventure.

TOOLS1

Re: Dirty carbs or ??

Administrator

In reply to this post by SECTION8

You say the engine is revving up, but, you are not picking up speed? If that is, so, you might have a clutch slipping.
TOOLS

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1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)

seestheday

Re: Dirty carbs or ??

In reply to this post by SECTION8

If you don't feel up to cleaning your carbs yourself, you can always send them away to get professionally cleaned. There are people that specialize in cleaning the cb750 carbs. One of the best manuals for cleaning them that I've seen is written by a carb cleaning service.

1981 CB750K with 900 cams
90K KM's, rebuilt head, rebuilt carbs, upgraded valve stem seals

My wife's recipe website that I'm trying to help promote: Strawberries for supper. Yes, I am a lucky man.

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LukeM

Re: Dirty carbs or ??

Administrator

There is an Asian MC salvage yard here that will ultrasonically clean a set of carbs for $60 US. It takes about an hour, and I'm told they come out factory clean.

Do a Google search for Rice Paddy Motorcycles. Their website isn't the swiftest, but they do answer the phone.

Luke M

Used to have a 1979 CB750L, sold it as a parts bike, now riding a slightly modified 1984 VT700C. Network/Field Engineer. Central OH, USA, Earth, Sol System, Milky Way Galaxy, Universe.

shinyribs

Re: Dirty carbs or ??

Administrator

I'm sorry.Seriously? Rice Paddy Motorcycles? That is awesome! HAHAHAHA! I will never forget the name of that business.

Scrappyike

Re: Dirty carbs or ??

In reply to this post by TOOLS1

I agree with Tools, had the same symptoms and it was the clutch.

American by Birth....TEXAN by the grace of God! I am the Texas Ambassador to Ohio.

1974 CB750 "La Cabrona"
1977 CB550 "Blue Bonnet"
1982 GL500i "The Grand Old Gal"
2008 CMX250 "The Piglet"

robs750

Re: Dirty carbs or ??

By your discription,it does sound like the clutch could be out of adjustment or the plates are worn.

When was the last carb service and valve clearance check?