You don't have to calibrate the heat sensor, after all assuming you use the plug type that fits in the head water jacket, it is simply a bead type thermistor sealed into the brass plug. So long as the thermistor performs properly there doesn't seem to be much to go wrong.
But it is comforting to know that when it indicates 65 degrees, it means 65 degrees.
You want to avoid castor type oils simply because they will gum up the carb and gum up the rings.
Typically we use R40 a castor type oil for running in, but when I mentioned that to the Castrol man, he was a bit surprised. But he did respond by saying that 'if it worked, I won't recommend that you change".
Elsewhere I have discussed about dyeing the oil to let yourself know what is in the can and what is in the tank. You can mix R40'd fuel and 747'd fuel in the tank.
15500 is likely to seem reasonably quick, especially if you are not racing, but it is off full racing pace. That said some quick drivers never seem to see those revs, so I guess they are smooth enough to gear down without losing punch in the corners.
As I said, for duration we would have to know what you mean by 15 hours duration. Do you mean 15 hours before you wipe the dirt off the engine or 15 hours before a major overhaul. The NKRA Blues seem to average about 80km/h on most tracks (average, not peak speed) so 15 hours driving would give you 1200 km / 1200 laps. So yes, that would appear to be well within the major overhaul time, but the 500 km minor overhaul is there because things have been found to be ready to change at that point and the engine is beginning to be losing edge in race terms.
It would probably be wise to lift the barrel at 500 km interval (ie: 500, 1000, 1500,) and look for signs of wear (circlips, ring gap, piston wear) rather than trusting to luck.
Equally, clean the bendix and re-oil , check the clutch bearing (needs a TDC stop) regularly.
Check the carb studs. some engines will have a long bearing section (the unthreaded bit) in the middle because they are designed to run with a restrictor in place. If you have these studs then the carb may not bolt down tightly without a spacer.
You can either pad out the gap with gaskets or, the easy thing, get a Formula Blue restrictor (Blue in colour), which is the same size as the carb throat and is therefore no restriction in theory. Or you can make up an alloy spacer.
The digital ignition means that the timing is governed by an engine map rather than a mechanical device. It is possible (I'm told) to get a different map or even reprogramme the one in the system, but there is the usual trade off that a different map makes demands on the rest of the engine that requires some other modifications advisable including a shorter life.
I presume that you already know how to set your carb both by the 'stroking' method and by the check-choke method as well as the piston/ plug condition method, starting off from the basic settings you were given.
Lastly, yes, once the throttle is closed the engine is 'dry', but being watercooled is much less sensitive to a dry sieze than the old aircooled 2 strokes. Unless of course you have been running rich and got excess fuel in the crankcase. generally you don't need to hand choke except during a run-in period. But you can run the engine as an aircooled motor, with lots of hand choking if the water coolant disappears, and even keep up a race pace by doing so....but it isn't recommended unless you really, really need the points.
(I have run a Blue without any carburettor or reeds at all, when a Junior was learning to cope with the smallest restrictor and kept drowning the engine. I expected it simply to turn over on the starter and throw the excess fuel out, but it started and kept running for a couple of minutes.
Not surprisingly the accelerator had no effect.)
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formula blue mechanics by 'Matty42' (17 May 2014 @ 9:51)
