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[PeteF]

I'll second Wellseal - great stuff. Cleans up with meths as well.

[Alan R]

----------cleans out your wallet as well !!! LES, 1/2hr is a bit OTT I would have thought. It says 5 to 10 mins. on the tube. Yes, it does flow nicely with a small artists brush ( Cue jokes re:- small artists, their brushes etc. ). My cow-gown top pockets always had a sticky patch where the brush was stored. To think that at the depot we used gallons---and I do mean GALLONS---of that stuff each day. Have a look at the valve arrangement in a 1970's Honda CB250/400 Dream and Superdream.-----2 in, 1 out. Single ohc, rocker actuated. fed by two constant vac. carbs, electronic ignition, 5-speed gearbox. Now, my understanding of valve size was that after combustion has taken place there is a greater volume of expanding gasses trying to get out than that which came in. Therefore, a "1-in & 1-out" set-up would have the exhaust as the larger of the two---all else being equal eg dwell times, lift etc.

[Les H]

Hi Alan, nope 1/2 hour is not too long...in fact you could leave it a week and it is still quite soft...hence the name non-drying. Too little "drying" time allows the stuff to completely squidge out of the joint..... Reason for inlet valve size exceeding the size of exhausts in higher performance engines is simple. Inlet side sees only atmospheric pressure to drive in the charge (or to be sucked in) whereas the exhaust gases are at a very high pressure and have the added advantage of being pushed out by the piston to drive out the gases, In less highly tuned engines leaving the exhaust valve as big as it is ie: the same size of the exhaust was seen to be necessary for the valve not to become too hot by the concentration of red hot exhaust gases flowing by it and its seat.

[Les H]

CORRECTION: "leaving the exhaust valve as big as it is ie: the SAME size of the INLET VALVE was seen to be necessary ETC ETC.