Advice on using choke to stop heat seize on long ride

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Avantone
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Anyone played with feeding atomised water into the charge? (cheaper than petrol), and didn't CE try using a thumb activated screen wash motor to inject water into the header a few years back (apologies if I got that wrong).

I'd also considered trying a pop off valve to open up a 2nd tail pipe and reduce exhaust pressure when things got too hot.
Tony

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Lamaddict
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I've used the choke to cool the engine down and it works. I'd be interested to calculate the main jet size plus the choke, would it add an extra 10 for a Dellorto, for example?
nelson pk
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Muppet wrote:think dat was wot I was wus tryin t be gettin over in me idiots post earlier :mrgreen: y can only put it rite usin choke ifin its wrong t start with or so clse t lean anything tips it over the edge,
Very true sir!
Lamaddict wrote:I've used the choke to cool the engine down and it works. I'd be interested to calculate the main jet size plus the choke, would it add an extra 10 for a Dellorto, for example?
It will cool the temp of the motor no matter if your scoot is jetted right because you are in effect over jettting it on say on a correctly jetted scoot and compensating on a lean jetted scoot.
If you do it on a correctly jetted scoot it wil still bring the temp down but you dont want that if your scoot is jetted correctly as the temp should be safe.
The point is that if you have jetted the scoot correctly you should not need to do this unless an air leak issue arises or an issue that Adam stated in a previous post.

If you are getting symptoms of overheating on your road bike after many miles of cruising and your compression, timing, fuel octane, exhaust,seals and gaskets, plug rating are ok you haven't jetted correctly.
A lot of paople when checking jetting just go up the road 1/4 of a mile and cut off to check plug colour.
This is no good when your talking of jetting a bike for travelling one hundred miles. You need to do the plug chop for longer distances each time up until about 6 miles to get a true reading (i say 6 miles because this is what i have heard/ read in 2 stroke books) obviously changing jetting in between should you need to.
Ricko
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[quote="Adam_Winstone"]I agree that a choke can be used to bring down temps, indeed, I do that if I feel a bike is running hot or weak, then I sort out the issue (e.g. correct my jetting or timing, dump rubbish fuel, etc). However, the point that I was trying to support is that choke operation to rectify a jetting problem would/should not be necessary on a correctly jetted road bike. Sure, a thumb choke can be used to good use on a 'special' or road bike that you are trying to run at the optimum but it should not be considered as anything but a temporary correction on a well set up road bike.


Spot on. :)
soosh
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Stick on a retard box and if set up correctly,you will keep the motor cooler with say 16/15 degrees when your cruising/hammering along for some distance.I bought one some time back for my iron barrel but yet to fit it.
dirtyhandslopez
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Keep it simple. Run it fat(rich) with a cold plug for a long run-be packed, fueled, fire up the motor and get gone down the road. Get to site, park up, un pack. Re-pack, fire up and go home. After you have got home and have un packed again,jet for riding in town, jet skinny(lean). You haven't got to mess about with the choke then. Much the same as others have already said. Or take some jets with ya ;)
Gauges this that and the other are all well and good but they add unneeded complexities that can and will fail I reckon. If you are relying on those instruments instead of what you can hear(pinking,detonation,griding etc.) and what you can smell(leaking fuel, burning rubber) see(things falling off :) ) and feel(vibrations,heat), it's no longer simple.
Taking your eyes off the road when travelling at high speed to look at a guage probably isn't the safest thing in the world, doesn't matter how much the gauges cost or how well they are set up.
Off the soap box now...
That's not going anywhere...
cit205
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^what he said 8-)
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