Post race, methanol and castor oil

In the late 80's I changed the oil (R40) every other meeting and drained the carb after each meeting. Having ridden last weekend I looked in the float bowl today and found a jelly in the bottom of the bowl and around the float needle.
When using methanol and castor oil what are the recommendations post race and laying up over winter? In particular to remove any trace of methanol polluted oil from bearings.

I always drained the tank fuel lines and carbs after every meeting when using methanol. Stored methanol in a sealed container. It is poisonous.

Also squrted carb cleaner through the carbs and any filters to clear out any methanol from the carbs after every meeting.

I have never had any issues with modern castor oil. I changed it every few meetings or 2 hours or so of running. Over winter in a dry warm garage I would drain the oil. And refresh in spring. I did run a Commando type oil filter.

I'm sorry, I am naturally curious. With modern oils like Klotz why do you still use castor oil?

mean gene said:

I'm sorry, I am naturally curious. With modern oils like Klotz why do you still use castor oil?

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I've asked the opinion of several good classic riders and tuners. They say that when using methanol, caster oil copes with any richness better than other oils which can wash off of the bore.

It was never a problem with Castrol R in my JAP speedway bike 55 years ago. As it was so often taken apart.
In my Manx I've used Morris C40 for the last 5 years. A castor based oil. I drain it after every race weekend. No signs of lacquers. But when in a open cup, (use it as cutting oil) after 2 or 3 years gets noticeably thicker.

Castrol told me that every other meeting was the MAX interval, ideally it should be every meeting!

The summary of what Castrol told me is: R is very thick when cold, so care is required to avoid wear during a cold start. And its molecular structure breaks down (permanently) if it gets too hot, and this is why it should be changed so frequently. But in between those lower and upper limits, when it’s at the correct temperature, its film strength and lubricity properties are second to none.

To support this, Dave Degens told me that ‘back in the day’ on cold days they used to warm up their R in a pan on the stove before putting it in the bike. And put the camping stove under the sump of the engine to warm it up. So they knew about the poor cold performance.

In those days though, the straight grade mineral oil available over the counter was very basic stuff, and R was in a different league.

As a petrol user not worried about methanol contamination, and not wanting to faff around as above, I decided that ‘overall’ protection was better with a top drawer synthetic oil.

Ref your methanol contamination question, I’d have thought it depends on your engine. If you’re running tight tolerances with no excess blow-by then I’d say it makes little difference that you’re running methanol. However if you know things are a bit loose and you have blow-by then that just reinforces the ‘change every meeting’ advice. But this is only an uneducated ‘petrol head’ guess !

Fast Eddie said:

Castrol told me that every other meeting was the MAX interval, ideally it should be every meeting!

The summary of what Castrol told me is: R is very thick when cold, so care is required to avoid wear during a cold start. And its molecular structure breaks down (permanently) if it gets too hot, and this is why it should be changed so frequently. But in between those lower and upper limits, when it’s at the correct temperature, its film strength and lubricity properties are second to none.

To support this, Dave Degens told me that ‘back in the day’ on cold days they used to warm up their R in a pan on the stove before putting it in the bike. And put the camping stove under the sump of the engine to warm it up. So they knew about the poor cold performance.

In those days though, the straight grade mineral oil available over the counter was very basic stuff, and R was in a different league.

As a petrol user not worried about methanol contamination, and not wanting to faff around as above, I decided that ‘overall’ protection was better with a top drawer synthetic oil.

Ref your methanol contamination question, I’d have thought it depends on your engine. If you’re running tight tolerances with no excess blow-by then I’d say it makes little difference that you’re running methanol. However if you know things are a bit loose and you have blow-by then that just reinforces the ‘change every meeting’ advice. But this is only an uneducated ‘petrol head’ guess !

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Good info thanks. There is some blow by as the piston is on the loose side when cold - Cosworth told me it was a very high expansion forging.
I'll stick to changing the oil every meeting. Thanks.

Mike40M said:

It was never a problem with Castrol R in my JAP speedway bike 55 years ago. As it was so often taken apart.
In my Manx I've used Morris C40 for the last 5 years. A castor based oil. I drain it after every race weekend. No signs of lacquers. But when in a open cup, (use it as cutting oil) after 2 or 3 years gets noticeably thicker.

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Never thought to use discarded R as cutting oil. Must give it a try.

Castrol R turns any bike into an instant shit heap. My mate had an ex-works 350 Manx. The guy at Vacu-Blast said he could remove the baked-on Castrol R without removing the grey conversion coating from the crankcases. The magnesium crankcases came back gleaming silver. My mate kept them dry in a cupboard. Then he phoned me. I told him the coating was DTD931 conversion coating as used on planes during WW2. I found him a guy who does it for aircraft in Australia - he was just up the road from my mate's factory. He did a perfect job of replacing the coating. The price was, he wanted to see the bike after it had been rebuilt.
In my bike, I only ever use ordinary mineral oil when using methanol. When I finish racing, I completely drain the tank, lines and I remove the jet covers from the carbs and put them on a shelf for a while.
If your jetting is so rich that the oil is washed off the cylinder walls, your bike must be going backwards.
RICH IS NOT THE ANSWER ! - It is a common mistake.
If I race, I am silly - I help other guys go faster. If they can give me a hard time, I love it.

My 850 motor has cast iron barrels, so it gets hot. It might be an advantage when using methanol. I always start the motor with the enrichers open, and let the motor idle until it is hot before revving it. I never worry about excessive bore clearance. It is what it is.

You run straight fuel through , to clear the nitromethane residue / acid , out . On Model Aircraft engines .

Runniong it , after draining the oil tank & cleaning . On Mineral - with the return line into a jar - when its
flushed itself its obvious . Particuly if the oil lines are clear braided nylon . Then takeitfor aspin .

Id Think 100 Ocatane , same proceedure , with the advance back a touch , if manual . But DRAIN CARBS after . anyway. too .

A olde D. R. dodge , the auto Adv. is set ' notched ' ( a indent ) THROUGH THE GATE , the 600 SS will come off the line , with the rear tyre alight ( as it were - Smoking )
Auto Adv. is a darn sight more workable . Tho manual overide on top , would be advantageous .

YES . The Duc. & the XR H.D. would skid the rollers , ( and the big ends'd go ) So low rpm initially . AND kicking it thru , till oiled . Is a must .

ON A ROLLER : leave the ignition OFF . for 5 seconds .

The Corsair , cold start , was flick ( pump - pump ) foot , crank , catch . tease . Wrup wrup wrup . UNTIL . I put a starter & ignition SWITCH ( or two or three ) on it .

WHEREAFTER . it was ' turn starter ' ON ' . Observe Oil Pressure Guage . AT 80 = switch ignition cut out , to ' ON ' . AND it was running. Started itself . without a RUFFLE .

As It had pre lubbed all surfaces & primed the cylinders plus the unignited fuel insured RICH START . So Chock & accelerator pump manipulation were unessesary .
The Foot ( throttle ) Didnt Come Into It .
( were 11 switches aligned central . unlabled . All Down was OFF . ) As we said . on the ROLLERS , leave ign. OFF for 5 seconds plus ( count to find its mettle ) thereafter
itt should catch , without a catch . burp . or hiccup . might not even fart .

There was a Castro C R I 40 monograde . Petrol Diesel Turbo . Non detergent . in the 80's . Good Stuff . High this that & the other . good in the V 4 .

Matt Spencer said:

You run straight fuel through , to clear the nitromethane residue / acid , out . On Model Aircraft engines .

Runniong it , after draining the oil tank & cleaning . On Mineral - with the return line into a jar - when its
flushed itself its obvious . Particuly if the oil lines are clear braided nylon . Then takeitfor aspin .

Id Think 100 Ocatane , same proceedure , with the advance back a touch , if manual . But DRAIN CARBS after . anyway. too .

A olde D. R. dodge , the auto Adv. is set ' notched ' ( a indent ) THROUGH THE GATE , the 600 SS will come off the line , with the rear tyre alight ( as it were - Smoking )
Auto Adv. is a darn sight more workable . Tho manual overide on top , would be advantageous .

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I used to be in charge of 5 explosives laboratories. Do not use nitromethane. A couple of guys were using it in a speedway Vincent sidecar. In the way home from racing one night, the driver saw a trail of sparks in the rear view mirror of his car - the bike was burning. Nitro in pure methanol should be very stable. The Jesser Triumph which Ken Blake rode, used a blend of about one third each of toluene, methanol and nitro methane. The mix of nitro with a hydrocarbon is a bit like mixing chlorine bleach with petrol - unstable.
My mate reckons nitro is safe, because he set fire to some in a tray, and it burned quietly. I did not tell him that nitro compounds have a critical height. If it is too high vertically, when burned it goes bang.
Where I worked we used to burn gun propellant made of nitroglycerine and other stuff. After I had Ieft, somebody stacked some too high at the burning ground. In a building a kilometre away, several books jumped off a shelf. It burns slowly for a while then accelerates.

If you are starting the bike on rollers, select 2nd gear rather than 1st - the rear wheel spins faster when the clutch is engaged, and it is easier to start the motor. In top gear, one rev of the rear wheel probably turns the motor over once. In first gear you are probably trying to turn the motor over 6 times for one rev of the wheel. If your idle is set correctly, you should be able to fire the motor up using the enrichers - let it idle until it slows a bit, then take off the enrichers and let it idle normally. I do not rev my motor until it is hot, and the oil is circulating.
It is great to find out that people are still using methanol - it is the best way to go racing.

acotrel said:

If you are starting the bike on rollers, select 2nd gear rather than 1st - the rear wheel spins faster when the clutch is engaged, and it is easier to start the motor. In top gear, one rev of the rear wheel probably turns the motor over once. In first gear you are probably trying to turn the motor over 6 times for one rev of the wheel. If your idle is set correctly, you should be able to fire the motor up using the enrichers - let it idle until it slows a bit, then take off the enrichers and let it idle normally. I do not rev my motor until it is hot, and the oil is circulating.
It is great to find out that people are still using methanol - it is the best way to go racing.

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Methanol is easy to use.

But as far as I know it is only legal in Australia and New Zealand. And then only in a few classes.

So for 95 % of racing around the world.

Forget it. !!!!!

acotrel said:

Castrol R turns any bike into an instant shit heap. My mate had an ex-works 350 Manx. The guy at Vacu-Blast said he could remove the baked-on Castrol R without removing the grey conversion coating from the crankcases. The magnesium crankcases came back gleaming silver. My mate kept them dry in a cupboard. Then he phoned me. I told him the coating was DTD931 conversion coating as used on planes during WW2. I found him a guy who does it for aircraft in Australia - he was just up the road from my mate's factory. He did a perfect job of replacing the coating. The price was, he wanted to see the bike after it had been rebuilt.
In my bike, I only ever use ordinary mineral oil when using methanol. When I finish racing, I completely drain the tank, lines and I remove the jet covers from the carbs and put them on a shelf for a while.
If your jetting is so rich that the oil is washed off the cylinder walls, your bike must be going backwards.
RICH IS NOT THE ANSWER ! - It is a common mistake.
If I race, I am silly - I help other guys go faster. If they can give me a hard time, I love it.

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"Castrol R turns any bike into an instant shit heap."

Have you actually used Castrol R in the past 20 years?

This is WRONG WRONG WRONG.

The formula has changed through the years. Modern Castrol R is little different in the mess it makes compared to any other modern oil.

Sorry mate but most of what you post is very very out of date. We raced bikes in the Manx GP last week. Racing 50 years ago is not racing today. Even on old bikes like Velos and AJS 7Rs.

So Castrol R is no longer vegetable oil - so how does it mix with methanol ? Sounds strange that if the formulation has changed - the name has not. There was something else we used to use with methanol in two strokes - I think it was Castrol M. In the 1960s Castrol R used to turn into an insoluble layer on engines. In Australia, methanol is legal on speedway, and in Period 3 and Period 4 historic racing (pre 1973). I would be surprised if Speedway Jawas in the UK did not still use methanol - that is if you still have speedway and grass-track racing. In the 1970s when TZ350s were the go in road racing, my mate used to specialise in putting them on methanol. Fuel checks were never done. With two strokes, methanol is silly stuff - the wear rates are too high. But it really makes them go. The problem is that drilling a smaller hole in a jet is not so easy. A lot of guys who have four-strokes use 0.120 inch needle jets with methanol. It is OK if your motor has 12 to 1 comp. With standard compression in a four stroke, I would start at 0.117 inch. But I make my own needle jets, so going smaller is not a problem. Drilling the complex needle jets of VM Mikunis is very expensive, if you are buying small jets and drilling them. I was lucky with the T250 Suzuki I built. One of my mates had a T20 on methanol and told me the needle jet size.
My brother has a 750cc H2 Kawasaki two-stroke motor on methanol, in a speedway sidecar. It is idiocy - nobody needs a bike that fast - it is just dangerous. His 500cc H1 sidecar is fast enough to win any sidecar race on speedway. He has a jeweller friend who can actually measure the internal diameter of needle jets. Getting the needle jet size correct makes a huge difference to performance, especially with two stroke motors. Even the shape of the needles has a major effect, - even with my 850cc Norton motor.
I would never expect an Amal needle jet or needle to be right for anything as bought. There is a reason British bikes were usually slower in a straight line, than Japanese bikes of similar capacity in the 1960s and 70s.

It is still a castor based oil but has additives which means you no longer have issues leaving it in the motor. I recently stripped a motor which had run on methanol and then stood in dry conditions for 10 years with Castrol R in it and the inside of the motor was clean.

That said many modern race engines like Manx Nortons and G50s etc have been converted to plain bearing cranks and needle roller bearings on the rockers. People use modern synthetic oils for those motors.

I still use castor oil in my Dominator twin motor with pushrods and standard followers.

Would also add something like this to the methanol.

It was not the inside of the motor to which I was referring. In the 1960s, Manx Nortons had exposed valve gear. Some guys used to wrap the motor on foam rubber to soak-up the oil. Castrol R on your bike turns into varnish. I watched Steve Oszko washing it off his Manx with methanol. He was up to his elbows in it. Methanol oxidises in your body and becomes formic acid - burns brains. If somebody drinks it - in hospital, they fill them full of ethanol - the theory is the combination of the two alcohols reduces brain damage when they are oxidised and expired together.
So if you use it, always have a beer after the meeting.

Ok. When you said any bike into a shit heap I wasn't considering the specific cases of exposed valve gear. However you may find methylated spirits can help with cleaning that regard. I would certainly not risk using methanol to clean an engine. It is definitely poisonous and I immediately wash my hands if I touch it.

Many of the replica motors have also now incorporated covers to control the oil. The original hairsprings having been converted to coil.

acotrel said:

It was not the inside of the motor to which I was referring. In the 1960s, Manx Nortons had exposed valve gear. Some guys used to wrap the motor on foam rubber to soak-up the oil. Castrol R on your bike turns into varnish. I watched Steve Oszko washing it off his Manx with methanol. He was up to his elbows in it. Methanol oxidises in your body and becomes formic acid - burns brains. If somebody drinks it - in hospital, they fill them full of ethanol - the theory is the combination of the two alcohols reduces brain damage when they are oxidised and expired together.
So if you use it, always have a beer after the meeting.

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