1990 VFR750F cold start issue

I was having trouble finding this exact problem elsewhere on the site, so Ill post it here.


Only when its cold does my bike struggle to start. It turns over, and the battery is strong, but it takes a good 5 min on a cold day to get it going. It starts no problem when its warm.
You can tell that fuel is getting in, and it will eventually idle.

Other then that, it appears to drive and idle fine.

A bike mechanic friend suggested that I change the spark plug insulators, as they are a cheap part. Local Honda dealer couldnt find aftermarket ones for the bike in the computer, so I have to bring in one tomorrow and get them to match it up.

Ive ran a bunch of seafoam through it recently just because it was sitting over the winter.
also, after getting it to idle it will backfire a couple times then be fine

Thanks,

ken

 

I assume you are using full choke and no throttle when attemping to start? Sounds to me like the choke needs to be adjusted or the carbs could use a proper cleaning especially since the bike sat for while. Did you drain the gas out and put fresh gas in after storing it? Also after attempting to cold start it several times have you checked to see if there is gas in the carb bowls?

Also just to let you know that you should never engage the starter on the bike for more than a few seconds at a time. If the bike doesn't start within the first few seconds you should let the bike rest for a minute before trying again.

Rollin

 

This isnt a problem that just started after storage. It did it last year as well.
All the gas had been drained out a couple weeks ago and fresh gas with seafoam went in. Ive gone through 2 tanks so far.
I hold the starter for a few seconds and then stop and repeat until it works. usually takes a couple min, but only when its cold outside. It could sit for days in warmer weather and start up fine.

 

I agree with a proper carb clean.

 

Common issue if you haven't wire-cleaned the enrichener circuit long brass tubes.

Your enrichener circuit is not getting fuel cuz the tubes are blocked with crud, and seafoam won't help much.

 

Had the same issue with mine. I had wet-fouled my plugs. Took them out, cleaned them, and has started perfectly ever since. Did this after running can of seafoam through as well. good luck

 

Yes, fresh, clean plugs help alot with starting and are much easier to do than carb work so try that first. If no improvement, dig into carbs.