Author Topic: CR750 Running (or not running!) issues  (Read 1290 times)

Offline moorey

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Re: CR750 Running (or not running!) issues
« Reply #30 on: December 03, 2018, 04:28:57 PM »
I use super unleaded in all my bikes to avoid the thernol related problems - until it gets put in that too!
Seemed to have sorted problem (see previous post) - duff plugs.

Glad to hear you have sorted it !
The only super unleaded that has no ethanol added is Esso Synergy Supreme, all the other brands "Shell" "BP" etc all have ethanol added, usually 10% & this is going to increase...  >:(

Unless it has altered very, very recently Our local Sainsbury was unleaded up to 8% and Super Unleaded 3%  As I asked.

Offline philward

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Re: CR750 Running (or not running!) issues
« Reply #31 on: December 03, 2018, 10:50:26 PM »
Just checked and BP Ultimate has no ethanol in as well - think there's a post on ethanol in fuel on the forum

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Offline royhall

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Re: CR750 Running (or not running!) issues
« Reply #32 on: December 04, 2018, 06:53:50 AM »
The EU was going to enforce the use of ethanol in all fuels (including diesel) from April 2017 but it doesn't appear to have happened. Probably too busy with Brexit. BP Ultimate in the North West is definitely still ethanol free.

This is the link:  http://www.sohc.co.uk/index.php/topic,8911.0.html
« Last Edit: December 04, 2018, 07:52:50 AM by royhall »
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Offline CR750

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Re: CR750 Running (or not running!) issues
« Reply #33 on: December 04, 2018, 11:34:33 AM »
I had this reply from BP :- dated 2014

Thank you for your email concerning the fuel sold by BP.

In "most regions" of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded).
This may of course change in the future as the specification allows up to 5%
. If there will be any changes, these will bw shown on the pumps and at the stations.
BP ultimate will never have more than 5% ethanol until January 2017  when it could be increased to 10%

dated 2018, Shell & Ethanol. in the UK, Shell regular unleaded and Shell V-Power unleaded are likely to contain some ethanol, but it will not be present at more than 5% (in accordance with current UK specification requirements
« Last Edit: December 04, 2018, 11:39:27 AM by CR750 »

Offline moorey

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Re: CR750 Running (or not running!) issues
« Reply #34 on: December 04, 2018, 07:54:39 PM »
I had this reply from BP :- dated 2014

Thank you for your email concerning the fuel sold by BP.

In "most regions" of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded).
This may of course change in the future as the specification allows up to 5%
. If there will be any changes, these will bw shown on the pumps and at the stations.
BP ultimate will never have more than 5% ethanol until January 2017  when it could be increased to 10%

dated 2018, Shell & Ethanol. in the UK, Shell regular unleaded and Shell V-Power unleaded are likely to contain some ethanol, but it will not be present at more than 5% (in accordance with current UK specification requirements

So this contradicts your original post on ethanol percentages then.

Glad to hear you have sorted it !
The only super unleaded that has no ethanol added is Esso Synergy Supreme, all the other brands "Shell" "BP" etc all have ethanol added, usually 10% & this is going to increase...  >:(





Offline CR750

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Re: CR750 Running (or not running!) issues
« Reply #35 on: December 04, 2018, 08:30:11 PM »
I had this reply from BP :- dated 2014

Thank you for your email concerning the fuel sold by BP.

In "most regions" of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded).
This may of course change in the future as the specification allows up to 5%
. If there will be any changes, these will bw shown on the pumps and at the stations.
BP ultimate will never have more than 5% ethanol until January 2017  when it could be increased to 10%

dated 2018, Shell & Ethanol. in the UK, Shell regular unleaded and Shell V-Power unleaded are likely to contain some ethanol, but it will not be present at more than 5% (in accordance with current UK specification requirements

So this contradicts your original post on ethanol percentages then.


No Not Really
I honestly don't think the Petrol Companies themselves are giving us the true content of ethanol in their fuel .
also I do know is its a waist of time asking the petrol station attendants about ethanol content I don't think half of them will know what it is..

why don't you try contacting the petrol companies above by email or letter & see what info & figures you will get
« Last Edit: December 04, 2018, 08:34:36 PM by CR750 »

Offline royhall

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Re: CR750 Running (or not running!) issues
« Reply #36 on: December 04, 2018, 09:22:42 PM »
Believe what you want from the company's front office, 3 weeks ago BP Ultimate in the North West had no ethanol, I tested it myself. It's very easy to do so why not give it a go and see what the results are you may be surprised.

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Offline moorey

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Re: CR750 Running (or not running!) issues
« Reply #37 on: December 05, 2018, 12:56:10 AM »
I had this reply from BP :- dated 2014

Thank you for your email concerning the fuel sold by BP.

In "most regions" of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded).
This may of course change in the future as the specification allows up to 5%
. If there will be any changes, these will bw shown on the pumps and at the stations.
BP ultimate will never have more than 5% ethanol until January 2017  when it could be increased to 10%

dated 2018, Shell & Ethanol. in the UK, Shell regular unleaded and Shell V-Power unleaded are likely to contain some ethanol, but it will not be present at more than 5% (in accordance with current UK specification requirements

So this contradicts your original post on ethanol percentages then.


No Not Really
I honestly don't think the Petrol Companies themselves are giving us the true content of ethanol in their fuel .
also I do know is its a waist of time asking the petrol station attendants about ethanol content I don't think half of them will know what it is..

why don't you try contacting the petrol companies above by email or letter & see what info & figures you will get
Ask the retailer it's on their spec sheets what they receive from the distributors . I asked the girls on the tills who didn't know the content but said they would ask and took my number. A day later I got a call from Sainsbury's head office with the information. It's not a secret and I didn't pluck my figures out of thin air.

Offline royhall

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Re: CR750 Running (or not running!) issues
« Reply #38 on: December 05, 2018, 07:13:23 AM »
The key words are "likely to contain ethanol". Not all BP does it depends where it's delivered from. Only way to know for sure is to test it yourself. It takes a couple of minutes to do, and is so important during the winter layup.
« Last Edit: December 05, 2018, 08:12:56 AM by royhall »
Current bikes:
TriBsa CCM 350 Twin
CB350F in Candy Bacchus Olive (still smoking on pot 4 Ggrrrrrr)
CB750F2 in Candy Apple Red
CB1300SA in Black
Triumph T100C
Suzuki GS1000HC (DHL morons ruined my tank)
CB450K0 Black Bomber (current project)

Offline Laverda120

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Re: CR750 Running (or not running!) issues
« Reply #39 on: December 05, 2018, 10:22:27 AM »
It is possible to buy a kit that separates the ethanol from the petrol. It was tested by Rupert Paul in Classic Bike a couple of years ago. The downside is obviously you need to buy the fuel in Jerry cans, take it home and separate it using the kit before filling your tank with the good fuel. This will be a real pain but we may not have a choice soon.

Offline CR750

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Re: CR750 Running (or not running!) issues
« Reply #40 on: December 05, 2018, 11:34:17 AM »
[quote author=CR750 link=topic=17651.msg152447#msg152447
I had this reply from BP :- dated 2014

Thank you for your email concerning the fuel sold by BP.

In "most regions" of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded).
This may of course change in the future as the specification allows up to 5%
. If there will be any changes, these will bw shown on the pumps and at the stations.
BP ultimate will never have more than 5% ethanol until January 2017  when it could be increased to 10%

dated 2018, Shell & Ethanol. in the UK, Shell regular unleaded and Shell V-Power unleaded are likely to contain some ethanol, but it will not be present at more than 5% (in accordance with current UK specification requirements

So this contradicts your original post on ethanol percentages then.


No Not Really
I honestly don't think the Petrol Companies themselves are giving us the true content of ethanol in their fuel .
also I do know is its a waist of time asking the petrol station attendants about ethanol content I don't think half of them will know what it is..

why don't you try contacting the petrol companies above by email or letter & see what info & figures you will get
[/quote]
Ask the retailer it's on their spec sheets what they receive from the distributors . I asked the girls on the tills who didn't know the content but said they would ask and took my number. A day later I got a call from Sainsbury's head office with the information. It's not a secret and I didn't pluck my figures out of thin air.....  neither did i
Quote:-
I also enquired about it at our local Sainsburys petrol station last year & I was told it had at least 5% ethanol in the super unleaded. I personaly would not buy any supermarket fuel for my bikes.

https://www.esso.co.uk/fuels-faqs
« Last Edit: December 05, 2018, 11:45:45 AM by CR750 »

Offline philward

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Re: CR750 Running (or not running!) issues
« Reply #41 on: January 08, 2019, 10:57:40 PM »
Had some time over Christmas hols to try and cure a intermittent popping/misfire on the overrun and tick over – to no avail!
Bike runs fine when accelerating and on a steady throttle but pops at tick over and when de-accelerating at lower revs. Its only on number 3 cylinder.
At the start of this post, I had problem of starting (suddenly) and the misfire – as per previous posts (and your help) cured the starting with the D7 plugs but mis-fire remains.
Plugs all between sand and brown (not black) – although not really had decent run
This is my thoughts
Can’t be ignition and coils as fire on 1 - 4 and 2 – 3 at once. Done compression test and 135 on all 4 cylinders (off kickstart as no starter motor fitted). Plugs new and moved caps on 2 and 3 with no change.
Just used a colortune and at tickover number 1 & 4 bunsun blue and 2 & 3 nearer white - adjusting airscrew on 2 & 3 makes no difference to colour of spark (although engine tone obviously changes slightly) – its more difficult to see flame colour on number 2 & 3 due to having to  look via a small inspection mirror (colortune mirrored tube hard to fit due to Boyer coil setup in the way) – hence I might not be able to accurately assess colour.
Just taken carbs off tonight to re-check number 3 carb. Thought I’d carefully check the fuel level in float bowls and removed bowls with fuel still in. Noticed that 1,2 and 4 has same level of fuel but number 3 had lower fuel level by 3 – 4 mm! I’m guessing that this may be the issue - weak mixture causing the popping (although no issues on accelerating?)
So, to increase the fuel level, I think I should decrease the float to body measurement by 3 – 4 mm?
Your opinions much appreciated!
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Offline MrDavo

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Re: CR750 Running (or not running!) issues
« Reply #42 on: January 08, 2019, 11:36:21 PM »
In my experience popping and banging on the overrun, but otherwise running ok, sounds like an air leak into the exhaust, perhaps at the head / pipe joint.

Worth checking first  before you play around with float levels.
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Offline philward

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Re: CR750 Running (or not running!) issues
« Reply #43 on: January 09, 2019, 08:51:19 AM »
In my experience popping and banging on the overrun, but otherwise running ok, sounds like an air leak into the exhaust, perhaps at the head / pipe joint.

Worth checking first  before you play around with float levels.
Thanks Dave - I'll check this weekend. The header to head joint design is very basic on the the race exhaust so quite probable

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Online andut

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Re: CR750 Running (or not running!) issues
« Reply #44 on: January 09, 2019, 08:55:39 AM »
Phil, 

Popping on the overrun / idle is a classic lean mixture symptoms and the lower fuel level in the chamber is an excellent place to start - sure that will go a long way to fixing yout problems.

Andy