Manshed day in Nowra

[ribbert]

Why would they put the rev ceiling 2.5 thou higher than the red line, at those revs you've gone past the peak power and torque outputs and it'd be like flogging a dead horse.

I've had mine to a bit over 10 thou and its fairly howling, and even though it might be possible to go higher, mechanical sympathy stops me from doing it. If they do have a limiter, I haven't reached it and never will.

Yep, I'm with you Tony, my bike sees near redline a lot but I can't see the point in revving it beyond max power and it's like finger nails down a blackboard seeing one revved way beyond it.

Undersquare pushrod motors can't generally be revved hard enough to self destruct but the FJ, with it's dohc and 4 valve design, possibly could.

So, what limits FJ engine speed, an erratic limiter randomly fitted to some bikes and not others or reaching max volumetric efficiency or perhaps something else?

Noel

[FJools]

They are more a protection from a missed gear or false neutral.
If you are on the case and revving to near the redline, any missed gear could send the tacho way past that 12,000 mark.
That would be my expanation but again, you would maybe expect it to be set around 10,500.

Perhaps a tuned race motor could safely get up there ?

[ribbert]

They are more a protection from a missed gear or false neutral.
If you are on the case and revving to near the redline, any missed gear could send the tacho way past that 12,000 mark.
That would be my expanation but again, you would maybe expect it to be set around 10,500.

Perhaps a tuned race motor could safely get up there ?

Yes, you can make an engine rev harder and produce more power at higher RPM but the strength of the components remains the same (and more likely to fail)
If I'm not mistaken, Legend's car engines only last a couple of seasons (correct me if I'm wrong) and mechanical failure not uncommon, not something you hear much of with FJ's on the road and Randy has rebuilt some 200 engines. That's a lot of rebuilds for engines that only do a small number of hours per season.

Keep it under redline!

Noel

[simi_ed]

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Mod (Pat?), please delete ...

[simi_ed]

Noel, I feel for you with your dents.  I had a similar experience when I removed my rear wheel to do wheel bearings.  But I CAREFULLY used the needed BFH with a punch to ONLY hit the axle, not the muffler. I found the axle bone dry, which is not how I install (much of) anything.  

The axle for some reason was difficult to remove and I watched nervously as he exchanged hammers for heavier ones. I saw what I thought was the hammer glancing off the muffler a couple of times but then forgot about it...until today!

Finally cleaning my bike after the trip I noticed this:



As you can see, the axle is well below the muffler.

He also snapped off one of the chain oiler nozzles but I noticed that at the time.

Having gone to so much trouble to keep them looking good all these years it's very disappointing to see them damaged so needlessly, not even a good story or a limp to go with it.

The last time someone else worked on one of my vehicles it was the bike shop rebuilding my Sturmey Archer 3 speed hub when I was 12. Hopefully it will be another 50 years before anyone else touches my machines again.

Grrrrrrrr.

Noel