I dunno about _all_ race engines, but on my 4 stroke m/c race bikes, one
will not heat up (and run/carburate well) unless driven pretty hard (after
initial start/warm). the carbing is the worst problem--it's so hair
trigger that you really only get a small degree band (compared to street
tune) to work with. I'd imagine that e.f.i. helps this a lot, but I dunno
what full on f1 engines would do. I've heard of plug fouling, and low
temp problems on 4 strokes, but they're comparatively rare, and they seem
to be decreasing in frequency over time.
the other bike doesn't seem to car, but that is more because it runs what
we'd call constant velocity carbs.
_two_ stoke racing, on the other hand, is a completely different matter.
you can get plug fouling, cold seizures, _terrible_ carbing and general
crappy performance until they're heated up, depending on tune. on the
other hand, you also get overheating problems. they are much more
sensitive.
I'd bet there are smaller problems on any carbed race car until operating
temp is reached, just because race engines are usually designed to run in
a specific pawerband for max. power, and the carbs are tuned that way.
plus, the hotter and engine is the better the performance (up to a point).
I think it's more a matter of the design being set @ xxxxx-xxxxx r.p.m.,
and you'd like it to be there as often as possible, 'cause you'd like to
win.
scott
On Tue, 18 Jan 2000, Dean Dashwood wrote:
>
>
>
> Just a thought - would a race engine (I'm talking Formula 1 now, not modified
> street cars) have problems keeping oil pressure up, or any similar
> engine-speed-related stuff, if it was constantly driven at lower revs than it
> was designed for? I doubt if this has any relevance to the Honda, I'm sure it
> has no relevance to LBCs, it's just something that occurred to me reading
> Scott's mail.
>
> Dean
> ---------------
>
>
> Date: Mon, 17 Jan 2000 01:26:11 -0500 (EST)
> From: Scott Hall <sch8489@garnet.acns.fsu.edu>
> Subject: Re: honda s2000 (was Re: Nitrous Oxide)
>
> On Tue, 11 Jan 2000, Joe Curry wrote:
>
> > Yes, Nik; That's precisely the point. The S2000 engine was designed
> > apparently taking many finer points from Honda's Racing effort. All
> > aluminum block and head reduce weight, high power band means that in
> > order to reach the output that is advertised, the engine must be kept up
> > in that range. Not doing so just could mean that the engine might not
> > be as reliable as the designers hope for. I bet the race engine
> > designers don't have much in the way of data from running their engines
> > for long periods at 3000 rpm of less! :)
> >
> > Joe
>
> I may completely off--I certainly don't know everything--but I'd be
> willing to say solidly that running an engine at lower r.p.m.s is not
> going to hurt any engine, at least with regard to engine stress. on some
> racing engines and two stroke engines, you can have soot and cold fouling
> problems, but running a street engine at a lower than max r.p.m. will not
> shorten its life when compared to high r.p.m. operation. it will have a
> shorter operational life in that the owner is going to sell it when he (or
> she, ladies ;-) ) finds out how gutless it is below six grand, but you
> don't have to worry about mechanical stress/wear problems.
>
> scott
>
>
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