Author Topic: Difficult to start + backfires  (Read 2936 times)

Offline TheMechwarrior

  • Full Member
  • ***
  • Posts: 150
  • Thanked: 4 times
Difficult to start + backfires
« on: October 17, 2014, 03:16:38 PM »
All,

After letting my bike site out the winter I went to start her up and she's just not having any of it.
I've tried until the battery gives out each day over the last few days. I leave the battery on the trickle charger over night.

I've almost had it running, it began to idle a couple of times very sluggishly but never managed to keep it going for more than a few seconds.
What follows next is many repeated attempts to get it going often with a great big backfire.

Best attempts have been with 75% to 100% choke.

Anyone got any suggestions?

It's that time of the year again and I'd like to riding :)

Cheers,

Mech.
Honda CT200P
Honda CB250T
Honda CB250N
Honda CB400N
Honda CB750 4 (hard tail chopper with leather king queen seat)
Honda CX500
Honda CB900 Bol d'Or
Honda CBR600
Honda ST1100PY

Together Each Achieve More
 

Offline Brock

  • Tardis Tech
  • UNBELIEVABLE "5000 Posts" Member
  • ****
  • Posts: 8713
  • Thanked: 1692 times
  • White is the fastest
Re: Difficult to start + backfires
« Reply #1 on: October 17, 2014, 03:54:23 PM »
The fuel system is dry (carbies etc), plus stale fuel and maybe a bit of gunk in the carbs as well. Hook up jumper leads to the battery, and give her another go. Maybe a shot of aerostart/startyabastard to give it a good hit of burny stuff.

A good strong battery will help spin the starter strongly, as well keep the fuel pressure up and good spark

Brock
Asian Correspondent
2003 Honda ST1100PY



Ulysses #32829
STOC #8239
OzSToc # ??
Kinross WA
 

Offline TheMechwarrior

  • Full Member
  • ***
  • Posts: 150
  • Thanked: 4 times
Re: Difficult to start + backfires
« Reply #2 on: October 17, 2014, 04:17:48 PM »
Thanks Brock.

So:

1. pull off the carbs and give them a good clean out
2. drain the fuel tank
3. replace the fuel filter
4. check the air filters

Can I jump start the bike by connecting my car battery to the bike battery or is that just crazy talk?

That should just about cover it?
I'll look around for some aerostart; the last time I used something like that was for an ancient dozer and from memory I squirted it in to the carby air intake?

That sounds like one of my days this weekend will be spent on the bike :)

Cheers,

Mech.
Honda CT200P
Honda CB250T
Honda CB250N
Honda CB400N
Honda CB750 4 (hard tail chopper with leather king queen seat)
Honda CX500
Honda CB900 Bol d'Or
Honda CBR600
Honda ST1100PY

Together Each Achieve More
 

Offline alans1100

  • 1999 ST1100A
  • UNBELIEVABLE "5000 Posts" Member
  • ****
  • Posts: 6250
  • Thanked: 1161 times
  • Alan, Peterborough, SA
Re: Difficult to start + backfires
« Reply #3 on: October 17, 2014, 05:10:40 PM »
Not an issue with jump starting......even the 1100 (motor running of course) is good enough to start the car

My car's been sitting six months and only started once a month and it still fires up first time so I doubt fuel condition alone is your problem......I haven't put fuel in it since I was at Ceduna in March 2014.

I did have trouble starting the bike after timing belt, coolant system repairs and fuel filter but that's only because the fuel shut off valve is vacuum operated so unless the motor isn't turning over fast enough to create the vacuum to open the shut off valve then fuel to carbs is almost a no go.

From the old days with reluctant car starts ( fuel pump on the motor has to suck fuel from 3/4 car length away) I just added a few drops of fuel down each carb until the motor started to run on it's own. It'll cough and splutter a bit but that's normal

Personally if I was to not ride for any length of time I'd still start the bike every week or to at most
1999 :bl11  2004 :13Candy

FarRider #921- BR15, BR17, CR1

 

Offline Brock

  • Tardis Tech
  • UNBELIEVABLE "5000 Posts" Member
  • ****
  • Posts: 8713
  • Thanked: 1692 times
  • White is the fastest
Re: Difficult to start + backfires
« Reply #4 on: October 17, 2014, 06:24:55 PM »
Always fault find by doing the easiest thing first.

1. Jumpstart from the car. Making sure you dont crank over too long as you dont want to cook the starter.

2.  Check the fuel filter ( disconnect the carby end ancheck for fuel flow out, redirect fuel into a catch bowl of some sort, dont want to burn the bike)

3. Check air filter, while there try a little petrol or aero start in the carbs ( couple of drops should do)  and crank again. Bike should fire up, and should rum for a moment or two. Put cover back on (prime again first) try starting again.

4. If it runs, let it keep going to warm up. If not, connect battery charger, put tools away and jumper leads. Go inside, swear at bike, grab a beer sit and watch TV. try againt to start tomorrow.

5. Come out fresh with positive attitude, start bike first go and go for a ride, burn a tank of fuel. Return home happy and refuel.
Brock
Asian Correspondent
2003 Honda ST1100PY



Ulysses #32829
STOC #8239
OzSToc # ??
Kinross WA
 

Offline Yorkie

  • Pit Crew & Recovery Specialist
  • NR2016 Group
  • Legendary "1000 Club" Member
  • *
  • Posts: 1374
  • Thanked: 202 times
  • ST Legend
Re: Difficult to start + backfires
« Reply #5 on: October 17, 2014, 09:01:31 PM »
It has to be a fuel related problem, I have had mine running on 2 cylinders.
Brian 0418937173
Manager York Motor Museum

In the shed
1999 ST1100A
1971 CB750K2
1980 XV750
1977 GL1000
FR#720
CMRCWA #133
York,WA

So at what age does this "old enough to know better" kick in?
I believe in the "hereafter", every time I go to the shed I have to think "what am I here after"
 

Offline Totgas

  • Legendary Member
  • *****
  • Posts: 757
  • Thanked: 83 times
  • Everything is improved with "Flashing lights"
Re: Difficult to start + backfires
« Reply #6 on: October 17, 2014, 11:05:56 PM »

Anyone got any suggestions?

Move somewhere warmer.... Sorry.  :p  :p  :p
I acknowledge hardworking Australians no matter who they are or where they come from. All those who have contributed to this wonderful country deserve an equal share of gratitude for their contributions. To single any group of individuals out for special homage only denigrates the rest of us.