Difficult Kick Starts When Cold

[bcware]

My '78 is difficult to start (kick only) when the engine is cold regardless of ambient temperature. It often takes 10 or 12+ kicks to get it going. If I use a little starter fluid in the air filters it will start first or second kick. When the engine is warm it will start first kick every time.

I am wondering if this is related to my modifications or clutch.

I am running twin emgo shorty mufflers; they are very small and have a large exhaust outlet. I use MikesXS pod air filters. The carbs have been jetted and performance is good. My clutch friction discs were worn last time I inspected them, but I re-used them anyway.

Could a lack of back-pressure cause starting difficulties?

Would worn friction discs make using the kick-start difficult? I am not even 100% sure the kick-start uses the friction discs as I never bothered to study the internal design closely.

 

[drewpy]

You need to find the sweet spot for the bike when cold starting.

on the tracker its enricher on and throttle fully closed, when its warm there's no problem what i do.

 

[bcware]

I suppose I can fiddle with the choke and throttle more. I don't vary my routine much.

Does the kick start use the clutch friction discs or bypass them? I am still curious about that.

 

[drewpy]

yes, you need the clutch to work as the kicker uses the transmission gears to turn over the engine

 

[xschris]

Nice to see you again BC

 

[bcware]

Oh hi
Yes, I took a break for a little while. It is nice to see everyone here.

 

[frwinks]

if it starts easily with quickstart, then it might not be getting enough fuel. What size pilots are you running? Might be time to bump them up

 

[bcware]

I spent a zillion hours tuning the carbs. I have every pilot and main size for the bs34. In the end I think I stuck with +1 on the pilots and perhaps +2 on the mains.

Once the bike is warm it runs very well; the mains may even be a tad large for hot summer days. I suppose I could increase the pilot and see what happens. In the past I goofed the timing and thought it was a carb issue. Now that the timing issue has been resolved I may play with the carbs a bit more. This is all going to have to wait until spring though; it's been about 25 F here as a high recently.

I really just wanted to make sure the clutch and large exhaust outlets weren't a common issue with kick starting.

 

[xs400neophite]

25* as a high?!! Damn thats cold!!
Nice to hear from you again.
I use kickstart to help my battery out. If she wont start with the E-start I kick her over a few times and then use the E-start and usaully that does it. I also dont use the choke and throttle is fully closed. Once she starts I rev her up slowly to over 4000k RPMs and usaully she is good to go.

 

[drewpy]

on the standard bike, i just look at her and she starts.

such a good girl and never let me down in 6 years.

.....at this rate the wife will be in the garage and the bike in the bedroom

 

[bcware]

Don't let her read this post or you'll be in the dog house

 

[drewpy]

Don't let her read this post or you'll be in the dog house

she's in London ATM and doesn't like motorbikes anyway

 

[xschris]

My wife gave me my first xs400 as a b-day gift

 

[bcware]

You guys are both lucky

 

[OG-Rider]

The main thing with mine, hot, cold, or in between, is do not touch the throttle. Don't even look at it!!! When it's cold, use full choke. Starts first kick. When it's warm, no choke. Starts first kick. When it's in between, good luck!

 

[bcware]

I do have a tendency to give it throttle when cold. Maybe this is just user error!

 

[16VGTIDave]

Think about how our "choke" works. It isn't actually a choke, which would be another butterfly that closes above the venturi, to block air flow and increase fuel delivery.

What we have is actually called a start circuit. It adds fuel and air to enrichen the mixture and increase the idle speed. Opening the throttle will bypass the start circuit. This is why most of our bikes will stumble or even die when running cold on the start circuit and the throttle is opened.

Dave