Author Topic: 1972 CB450 starting issue - was running three weeks ago  (Read 1312 times)

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Offline Deav

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I’ve had this bike for about 10 years. Don’t ride it much these days but I start it up every 2-3 weeks to keep it working. Last time I did that it didn’t start.

Put a new battery in. I have spark. Fuel is flowing. Bowls are full. Emptied bowls and they filled back up. Cranking strong but not firing.

I’ve not touched the carb adjustments. I want to check the easy stuff before I start messing with settings that I know we’re fine.

It seems like a fuel issue. I sprayed started fluid in the carbs and it fires up strong and then bogs out.

My next plan is to empty the fuel tank, replace the fuel lines, and soak the carbs without disassembling them.

Anything else simple I might be missing?

Offline bryanj

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Re: 1972 CB450 starting issue - was running three weeks ago
« Reply #1 on: May 04, 2020, 02:13:54 PM »
I think you may well have blocked pilot jets
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline onepieceatatime

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Re: 1972 CB450 starting issue - was running three weeks ago
« Reply #2 on: May 04, 2020, 03:13:06 PM »
Probably the slow jets. I had the clean them out on my 74 CB450 to get it to run on both cylinders.
1965 CA77
1972 CB750K Ol' Sarge
1974 CB450K7
1977 CB750K7
1977 CB750K7
1980 CB650C
1982 CM450A
1997 GL1500SE

Offline tbpmusic

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Re: 1972 CB450 starting issue - was running three weeks ago
« Reply #3 on: June 29, 2020, 07:57:02 AM »
Old gas??
Old Hondas don't like that.
"If you can't fix it with a hammer, then it's an electrical problem"

Bill Lane
 '71 CB450 Mutant/ '75 CB200/ '81 CM200/ '71 C70M