Why won't it start?

^

I think you've discovered a grammatical error previously unknown to science
there.

 

It's a line trotted out on ukrm regularly, but I've never had it
happen. Every year since 1992 my bike has been put in the garage
around Oct/Nov and not startup until Feb at the earliest, sometime
later.

A few years back the TOG Tour in early May was the first time my bike
had moved for seven months.

Ah, I can't beat that /

 

Indeed, and one that I thought I'd managed to disprove. But I suppose
not everyone will be convinced.

Hah. When I had the now-Blaney 400/4 in my garage (having bought it
for J who never really got into biking once shed passed her test)
alongside the gixxer, I'd take it for a brief run perhaps once or
twice a year, tops, just to keep it running, like. So there were
almost certainly times when the petrol would have been in the tank for
two years or more. Never had problems starting it over the whole 4-5
years I had it.

 

Probably not an issue on most bikes. Nordwests with the Teikei two stage
carb do suffer from it. In fact even a fairly short period unused can
make them difficult to start even if everything else is tip top.
Fortunately the carb has a convenient drain screw so it is easily
rectified. Only the petrol in the float chamber seems to go off.
The theory, and I stress this is a theory, is that the most volatile
fraction in the fuel within the carb evaporates, even after 'topping; up
by opening the petrol tap.. A complete fresh float bowl full from the
tank often does the trick.

I don't know the science of it, but I know it has worked for me a few
times. TBF the somewhat all or nothing nature of the starter jet on them
doesn't help. I soon discovered that a good dodge is to operate the
'choke' progressively while cranking the motor over. It would often then
hit the sweet spot and fire up. Still Nordwests are 'special'. In any
case the best cure is to put FOAD CR33 smooth bores on them.


--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

As theories go, that one's been tested and found lacking. e.g.
http://groups.google.com/group/uk.rec.motorcycles/msg/d3225adb64ff0330

 

A carburettor is not a 'sealed container'. As I said, for most vehicles
it is not an issue. For some high compression singles left unused for a
while I'm not so sure. Note that just refilling the float chamber with
'old' fuel from the tank is sufficient.

So I'm not saying fuel does go 'off' in the tank. It could also be a
case of some water condensation gathering in the bottom of the float
chamber.

I have tested the refill the float chamber with fuel strategy on several
occasions, so empirically it works for me. Faced with a bike that
wouldn't start after being left for a while it would be the next thing I
checked after making sure there was a good spark.

Also, IME it's best to leave the petrol tap on for a reasonable time
before attempting to start any bike that has been standing for a long
period.

So, yes it's probably not a question of gone 'off', but just gone.


--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

Indeed, & not just high comp singles. If I leave my old Tig for even
just a few weeks, it gets unhappy about starting. Drain the floatbowls,
switch the tap back on, & it fires up instantly.

I now switch the petrol tap off a minute or so before killing the
engine to empty the bowls a bit, & it starts perfectly every time, even
after several months.

The Corvette started & ran fine on petrol that had been in the tank for
13 years. Likewise my old V8 Cherokee ran fine on 5-6 year old petrol.

So petrol in a tank doesn't go off to the point where it won't work,
but petrol in carbs can, & anyone who says differently is wrong. Simple!

--
Krusty

'03 Tiger 955i
'02 MV Senna (for sale) '96 Tiger (for sale)
'79 Fantic Hiro 250 (for sale) '81 Corvette (for sale)

 

There's cheap and there's crappy varieties though.

Yea, me and chargy things don't get on, as they're always flat when
you want to use them . and i'm too cheap to keep them plugged in
permanently, so the start and charge and a great gurt extension lead
does me fine.

P.

 

FWIW I left the old (Madras) REB 350 for 3+ years untouched. The fuel
smelled like paraffin the float chamber was a bit gunged up and dry,
as was the battery.

I gave the float bowl a bit of a clean (with stale petrol from the
tank), a decompress and a couple of dry kicks and it fired up first
real kick. Ok, there was a fair bit of smoke to start with but it soon
cleared. But then it was probably designed to run on paraffin in the
first place!

T i m

p.s. It was hearing that 'dob dob dob' on tickover than nearly made me
change my mind and keep it. It was a dear old thing, never leaked a
drop of oil and didn't miss a beat over the 5000 miles I had it.

 

Where can I buy one of these?

 

My experiences are with my ZZR600, ZXR750 and ZX-9R over a period of 15
years, and every winter.

Me neither.

 

Where I sold mine ....

http://www.haywards.co.uk/

T i m

p.s. I don't think it will really run on paraffin but I think they do
(or did) a diesel one. ;-)

 

I've never had the problem with injected engines either.

Some people refuse to believe anything they haven't had personal
experience of. If it wasn't for the Tiger, I might be in Ace's camp on
this. But because of the Tiger, I know categorically that it can happen
(& has to lots of others on both the Yahoo Tiger & trailriding groups
too).

--
Krusty

'03 Tiger 955i
'02 MV Senna (for sale) '96 Tiger (for sale)
'79 Fantic Hiro 250 (for sale) '81 Corvette (for sale)

 

Well let me know when you've tested it on every carb bike ever made, ok?

--
Krusty

'03 Tiger 955i
'02 MV Senna (for sale) '96 Tiger (for sale)
'79 Fantic Hiro 250 (for sale) '81 Corvette (for sale)

 

Oh, it does, but only over very long periods of time, like a few years.

 

My old 1200 Trophy was similarly reluctant. It would kick in on one,
then two, then three and finally the other three pots would sort of kick
the fourth one out of bed and it would be A-OK.

 

Has Ben still got that? Bloody nice bike, that was.

 

LOL

 

and I (kick) started the KTM at the weekend after optimating the
battery. It started 4th or 5th kick, after not running since last
August.

*nods*