The magazine for fans of classic and twinshock trials, motocross & enduros

Mr Angry

In those far off days he had a number of personas that would be ‘guests’ on his show and these personas were fascinating studies of character traits in us all, with each one being used at an appropriate time to add a comment to a news item or reader’s letter. One of his characters was Mr Angry (from Purley, apparently). Anyway, this character would get annoyed and yell ‘I’m so angry’ then slam the phone down.

I’m not at that stage... yet, but it’s a close run thing at the moment and I have been quietly advised that I’m actually thumping the keyboard as though I were chopping a mortise. But, I digress, what has got me so revved up is this ‘stuff’ being sold as petrol and its effect on vehicles.

Don’t worry there’s not going to be any political rant from me, but this subject of ethanol added to petrol – currently anywhere between five and 10 per cent of the volume of fuel – is causing all sorts of problems. Not only are there horror stories from the boating world where there are tales of entire craft melting because of the nature of ethanol, we’ll also ignore the impact on the food supply as land is turned over to fuel production and instead look at the impact on carburation.

I’ve just ridden in the second round of the PJ1/CDB Northern British Trials series and the B40 was not a happy bunny as we went along the road. It’s obvious when carburation is a mile out of adjustment as the bike will surge or splutter or run hot or vibrate. It’s this last situation that got me, vibration so bad that the silencer bracket cracked and all of a sudden things got very loud.

There have been carburation issues with the B40 in the past and it’s reasonably well documented in previous issues what I did to resolve them – listened to other people, took advice and then got someone who knows what to do to check over what I’d done. The improvement was excellent and for the best part of 18 months remained so. Even two other recently tackled trials that also have road work in them were no problem, but not the other Sunday.

The bike started first kick as usual, even chugging along the track to the start seemed fine... but out on the road I thought my teeth were going to slacken off.

Anything more than a third throttle was not even unpleasant, it was way past there and on into nightmare regions as we banged, surged, popped and roared our way round the 40 mile course. A change of plug made a slight improvement as did some impromptu needle work – no, I didn’t sit at the roadside and do a spot of embroidery to calm down but altered the clip on the needle – but still, things were not brilliant. The only change made to the bike, from it working well to being awful, was fresh fuel in the tank.

The ethanol in fuel has caused more problems for riders of old motorcycles too.

Sorting out a leaky tank used to be a simple job of draining out the petrol, giving the inside a quick clean then swirling round some tank liner, let it set, make sure the tap holes were clear, refit the tank and away you went. Not any more as ethanol will soften the liner so much that it can flow through the carburettor and block jets.

There’s also some evidence, though I’ve not seen it, that modern fuel can eat through alloy petrol tanks. Anyway, there are newer liners available in the marketplace to combat this extremely corrosive side of ethanol in fuel.

This stuff passing for petrol has other properties too as the seals and fuel hoses can be affected by it. What happens if the fuel hose isn’t compatible with ethanol is it will swell up and allow petrol to seep past the banjo connection. I had this very problem too at a trial a couple of years ago. I’d laid the B40 against a bank, went to walk the section and came back to see petrol running out of the carburettor. Not good, the only option was to snip the end off the hose and push it back on. A short term cure that lasted the rest of the day but it was only when I went to buy some new hose that the supplier advised ‘ethanol proof.’ So, watch out with this stuff and check your seals are ethanol proof too.

One thing I didn’t check out was the effect new fuel has on rust – maybe if it’s that corrosive it might just clean rust off metals which would have been a great help when sorting the inside of Project CanAm’s oil tank. Elsewhere in this issue you’ll see the latest stages of our new project bike.

Many of you will have seen it on our stand at Telford and the International Classic MotorCycle show at Stafford too.

A big problem was cleaning out the inside of the autolube oil tank. It forms part of the frame and was so full of crud that had oil gone in then this crud would soon have been transferred to the carburettor, which wouldn’t have been good. Still, we mixed up a de-rusting solution of De-Ox C and this stuff shifted it and made the inside of the tank look sparkly too!

Tim Britton,
Editor