Vintage and Classic Hondas

Bike runs but hard to start and low power

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Peterwh

Bike runs but hard to start and low power

I had a lot of difficulty getting my K8 to start tonight.

I swapped the carbs at the weekend and it ran fine afterwards but it was a very warm day around 95 I guess. Tonight the bike just wouldn't start it would fire occasionally but not catch. Eventually I got it to start after cranking it continuously for about 2 minutes.

When I got it to start it seemed as though it wasn't running on all four cylinders all the time. Number 1 took quite a while to warm up and number 2 never did get to the burn your wrist temperature even after riding it for 10 minutes.

I pulled the spark plug cap on number 2 and it seemed to run better when the cap was half on the plug than when it was pushed fully home.

You may have seen in another post hat I can't get all of the intake boots onto the carbs properly - I'm running a standard air filter box. Three off the boots are well engaged but number two isn't quite on properly. Could this cause that cylinder to run weak and lose power?

The only other thing I can think of is a faulty coil but wouldn't that affect two cylinders?

Any thoughts and ideas welcome. Thanks.

shinyribs

Re: Bike runs but hard to start and low power

Administrator

The cold pipes sound like pilot jet issues. The low power could be a result of weak ignition after prolonged cranking. But the SOHC bikes don't seem as sensitive to this as the DOHC's do, in my experience.

Honestly, I'd just get those boots on and sealed up well, the carbs synched ( will need a re-synch of that loose boot is leaking any at all) and make sure your battery is fully charged. But even then, the cold pipes at idle have ALWAYS pointed to plugged pilot jets in the past.

TOOLS1

Re: Bike runs but hard to start and low power

Administrator

In reply to this post by Peterwh

Are you referring to the boot between the carb and head, or the boot between the carb and airbox?
TOOLS

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Peterwh

Re: Bike runs but hard to start and low power

The boots between the carbs and the airbox

Re-run

Re: Bike runs but hard to start and low power

Administrator

Carb and airbox boots don't matter much. Usually though, it is a matter of turning the boot so it lines up better.

The cold pipes are either lack of spark, or plugged idle jets.

Pull the idle jets and clean them. I would also remove the plug cap and snip 1/5 inch off and put the caps back on. Could just be poor contact.

The ride IS the adventure. The destination is just to get gas!