Help needed with ST1100 Carbs

[Niall]

Hello,

I’m looking for help with my ST1100 pan European, I have recently replaced the carbs with a refurbed set and while the bike now runs and starts there is an issue, with what I think may be fuelling. If you look at the attached video still, you will see the exhaust headers are glowing red hot after a very short engine run on the ramp

Any help or advice on what route to take would be appreciated

 

[ST1100Y]

... the exhaust headers are glowing red hot...

brutally lean mixture?

 

[Slydynbye]

Hello,

I’m looking for help with my ST1100 pan European, I have recently replaced the carbs with a refurbed set and while the bike now runs and starts there is an issue, with what I think may be fuelling. If you look at the attached video still, you will see the exhaust headers are glowing red hot after a very short engine run on the ramp

Any help or advice on what route to take would be appreciated

What else did you do besides swapping carbs?
Set idle mixture screws? balance carbs? Change plugs?
Did you change Carb insulator boots?
How does it run?
What constitutes a short run? What is a ramp?
What does the Engine temp gauge read.
Any history on the "new" carbs?

 

[Uncle Phil]

brutally lean mixture?

That would be my guess also - never seen that with a ST1100 before.

 

[Oldbikefixr]

I've had mine for 11 years now.
Did rebuild the carbs a while back. I followed the Honda manual and used a vacuum gage set to balance them. No carb issues. No glow in the dark exhaust system.
Good luck with it. Let us know what you find, with photos if you can.

 

[Mellow]

We had an ST1100 member recently with a stuck closed thermostat... is it possible you're also getting that and it's overheating? Just throwing a dart.

 

[Niall]

What else did you do besides swapping carbs?
Set idle mixture screws? balance carbs? Change plugs?
Did you change Carb insulator boots?
How does it run?
What constitutes a short run? What is a ramp?
What does the Engine temp gauge read.
Any history on the "new" carbs?

Thanks for replying to my thread

Carbs were swapped, new carb insulator boots, new plugs, it is running ok considering it hasn’t run in 6 months and when it was running it was only running on 3 cylinders.

The short run was maybe 60 to 90 seconds tops.
Engine temp guage read cold

The “ new”carbs came from an 1999 ST1100 from Lithuania. They had been refurbished and were spotless, They were stripped, put through an ultrasonic cleaner and rebuilt with a new carb kit

Regards,
Niall

 

[SMSW]

The short run was maybe 60 to 90 seconds tops.

In your first post you said "after a very short engine run on the ramp"
Do you mean riding the bike uphill - i.e. under load? or do you mean sitting in your driveway idling?

 

[Slydynbye]

Thanks for replying to my thread

Carbs were swapped, new carb insulator boots, new plugs, it is running ok considering it hasn’t run in 6 months and when it was running it was only running on 3 cylinders.

The short run was maybe 60 to 90 seconds tops.
Engine temp guage read cold

The “ new”carbs came from an 1999 ST1100 from Lithuania. They had been refurbished and were spotless, They were stripped, put through an ultrasonic cleaner and rebuilt with a new carb kit

Regards,
Niall

OK that all sounds good.
What did you set the carb idle screws initially? I think it should be 2 full turns from a light seat. What kind of screws are they? a cross hatch as in this video

I think Motion pro makes one of that type

Or is it a D-shaped head? in that case you will need the proper tool 07MMA-MT3010B

Do you have a vacuum gauge to make the proper adjustments and balance the carbs?