Fuel .. a basic question

General purpose topics/chat goes in here
Member
Posts: 304
Joined: Tue Oct 24, 2017 11:05 am
Location: DEVON UK

Re: Fuel .. a basic question

Postby MalcW » Thu Jun 13, 2019 4:04 pm

If the valve seats need replacing anyway, or if you are intending to travel vast mileages at speed, then you could change them. Otherwise you should be fine. These days the ethanol content of fuel tends to be the problem.

Malc

Member
Posts: 104
Joined: Tue Aug 30, 2011 3:35 pm
Location: DEVON UK

Re: Fuel .. a basic question

Postby oldandsmelly » Thu Jun 13, 2019 4:07 pm

The question of unleaded fuel additives in old bikes and cars has fuelled many a lively debate in pubs up and down the country for years. I'm in the sceptical camp; My 500 single and 650 twin have done thousands of miles in my ownership and I haven't bothered with any additives or different valve seats and I haven't found any deterioration.


Personally, I think the whole unleaded fuel vs hardened seats thing in our machines is a red herring although others may feel differently.

Member
Posts: 6118
Joined: Wed Sep 01, 2004 12:00 am
Location: WEST SUSSEX UK

Re: Fuel .. a basic question

Postby SPRIDDLER » Thu Jun 13, 2019 4:58 pm

Welcome to the Forums, Ben.
This has been done to death on here ever since mother was a lad. If you were a subscribing member of the club you could search the tech Q&A info. but as a Guest your access is restricted and you will have a limited time to post on here. Have a look at this recent thread:

viewtopic.php?f=11&t=24843&hilit=valve+seat

And join the club ;)
I poke badgers with spoons.

Member
Posts: 257
Joined: Sun Oct 07, 2018 10:36 pm
Location: Essex UK

Re: Fuel .. a basic question

Postby Plugsnpoints » Thu Jun 13, 2019 5:21 pm

discokid wrote:
MalcW wrote: ..... These days the ethanol content of fuel tends to be the problem.

Malc



Yes, been reading about that .. as I understand .. tends to 'attract' water which forms a gel if left standing .. I don't expect to be doing many miles, so the bike will be standing about in the garage a lot of the time ... so only put enough fuel in for the miles expected to be done on a specific journey, keeping residual amount as small as possible?

My top tip is if you plan to lay up any petrol engine (including motorcycles)for a few months is to run it out of petrol, then put a small amount of lawnmower petrol in the tank. Then fire it up so it's in the system. Lawnmower petrol has a 5 year shelf life.


I took a 20 year old lawnmower carburettor apart which had been run on this from new, and inside it genuinely was immaculate. I use it on my mowers and even if you leave them for a year they always fire up without issues. I never have to strip carbs or flush out systems. It costs a bit more but saves a lot of hassle in the long run.

Member
Posts: 257
Joined: Sun Oct 07, 2018 10:36 pm
Location: Essex UK

Re: Fuel .. a basic question

Postby Plugsnpoints » Thu Jun 13, 2019 9:13 pm

discokid wrote:
Plugsnpoints wrote:
.... a small amount of lawnmower petrol in the tank. Then fire it up so it's in the system. Lawnmower petrol has a 5 year shelf life.




It not being April 1 I must assume this is serious .. but can't find any reference on line .. please elucidate ..

Hi, no it's not a joke. Look up Aspen 4 stroke, or Viking fuel. I bought some 4 stroke lawnmower fuel made by Stihl this weekend. Unleaded starts to break down after a few months. A cheaper option is Briggs & Stratton Fuelfit which you add to stabilise unleaded petrol. The proper mower petrol is far better in my opinion. Andy

Member
Posts: 257
Joined: Sun Oct 07, 2018 10:36 pm
Location: Essex UK

Re: Fuel .. a basic question

Postby Plugsnpoints » Thu Jun 13, 2019 9:16 pm

Plugsnpoints wrote:
discokid wrote:
Plugsnpoints wrote:
.... a small amount of lawnmower petrol in the tank. Then fire it up so it's in the system. Lawnmower petrol has a 5 year shelf life.




It not being April 1 I must assume this is serious .. but can't find any reference on line .. please elucidate ..

Hi, no it's not a joke. Look up Aspen 4 stroke, or Viking fuel. I bought some 4 stroke lawnmower fuel made by Stihl this weekend. Unleaded starts to break down after a few months. A cheaper option is Briggs & Stratton Fuelfit which you add to stabilise unleaded petrol. The proper mower petrol is far better in my opinion. Make sure you buy 4 stroke and not 2 stroke unless that's what you need! :) It's £20 for 5 litres from lawnmower outlets. I know it's expensive but it saves a load of hassle on long standing engines. They sell it in 1 litre containers as well. If you have rubber seals and o rings they do not deteriorate either. Andy

Member
User avatar
Posts: 613
Joined: Tue Mar 15, 2016 8:51 pm
Location: Lincolnshire, UK

Re: Fuel .. a basic question

Postby Pharisee » Fri Jun 14, 2019 7:30 am

I have four bikes... two Meriden Triumphs and two AMC machines. My Bonneville and my AJS M18 both have hardened valve seats for reasons that we don't need to go into here. Both of these bikes run on straight unleaded fuel, 97 octane 'Super' in the Bonneville and 95 octane 'Regular' in the AJS. The Tiger 90 and Matchless G3/LS don't have hardened seats so I run both of those on 97 octane unleaded petrol that has been dosed with Castrol 'Classic Valvemaster Plus'. Whether they actually need that or not, I'm not qualified to say but even if it doesn't do any good, I don't see it doing any harm.
Being a 'fair weather' biker, I don't use the bikes over winter. When they start speading salt, my bikes come off the road until the Spring. I drain the carburettors but not the tanks. I estimate how much petrol is left in each tank and add a suitable quantity of Sta-bil fuel stabilizer. Again, whether it's actually necessary or indeed, helps I don't know but I don't believe it can do any harm.

Next

Return to General Topics

Who is online

Users browsing this forum: ajsm18 and 20 guests