ESE's works engine tuner

[Drew]

Came off the taper.

Wonder if a second or gruntier key wouldn't stop that happening.

[F5 Dave]

Yeah one time at (band camp) Manfield I saw Ray Wilsons flywheel come off and came unwasf close to beaning Pete Sales who was flagging. F5 you were there, the same day you rode my first version TZR100.

Oh don't remember that but I remember riding your bike clear as if was this afternoon. opened my eyes to what was possible. Seen cranks sheared off clean at the crankweb. Always a big flywheel attached. At least 3 suzukis

[husaberg]

Keys don't hold on stuff, the taper does...... if it came off the nut was loose and or the taper was shagged. keys are only the locating device on flywheels.
lap it on, nut up tight, they stay there....... I learnt that lesson after I lost my flywheel a couple of times

[Kickaha]

if it came off the nut was loose and or the taper was shagged.

Could have been either Diesel Pig was always hard on gear

[jasonu]

Wonder if a second or gruntier key wouldn't stop that happening.

I wonder if PROPERLY torqueing the nut to the shaft might have stopped the flywheel coming off.....

[Muciek]

I have a question about boost porting (picture on the bottom of post). Does this type of boost port grinded in liner in depth around 5 or 6mm is worth doing ? I tried this one back few years ago but I was more in style "do a shitload of ports in cylinder " didn't even know that something like STA is existing
And I'm attaching a photo of a piston which was used around 150km, would this help to get the black spots off the piston? Boost port cannot be any wider because ring pins are 2mm from it. Ducts are "crappy ones" not much to be done with them. Thanks in advance.

[wobbly]

So Sic won 6 races in 2008 and took the 250 title, by your way of explanation Drew then he was a genius that year.
Trouble is he won 6 races in 2009 and lost the title, as so many of the other points were shared out between Aoyama and the Aprilia satellite teams with so called no names on board.
One race has shit all to do with it - explain then the 2006 Moto year where there were 8 race winners, Hayden won 2 and took the title.
Were all those riders only average then - tell Rossi that.
I still come back to the later results, short lived as they may have been, where Sic was on the Moto pace instantly, Aoyama was and still is nowhere, his accident hurting his back badly made no difference before or after.

[husaberg]

I have a question about boost porting (picture on the bottom of post). Does this type of boost port grinded in liner in depth around 5 or 6mm is worth doing ? I tried this one back few years ago but I was more in style "do a shitload of ports in cylinder " didn't even know that something like STA is existing
And I'm attaching a photo of a piston which was used around 150km, would this help to get the black spots off the piston? Boost port cannot be any wider because ring pins are 2mm from it. Ducts are "crappy ones" not much to be done with them. Thanks in advance.

Yamaha TD1 b or C had that style, i have some drawings somewhere but they look exactly like what you have posted out of bell......... worth while? not a clue......

[wobbly]

The auxiliary ports fed thru the piston do " work " in that they are better than none at all if aimed correctly but the flow is very compromised
having to get thru the hole and into a slot.
Can you give us a picture of the cylinder base - is it possible to cut B ports with ducts all the way down to the case.
These would exit directly across the piston, as opposed to working like auxiliary boost ports aimed upwards next to the main boost.

[Muciek]

There is pic of base. Not much space to do anything. You mean to do something like on second photo, but aimed like boost port(ie 60*).

[F5 Dave]

I wonder if PROPERLY torqueing the nut to the shaft might have stopped the flywheel coming off.....

Only takes a little pick up to stop the taper working, quick lap (dance?) should fix, but won't help when the flywheel ejects still firmly gripping the shaft (Ooo-er vicar)

[Yow Ling]

Only takes a little pick up to stop the taper working, quick lap (dance?) should fix, but won't help when the flywheel ejects still firmly gripping the shaft (Ooo-er vicar)

A wee zap with the mig should stop it falling off

[TZ350]

Keys don't hold on stuff, the taper does. keys are only the locating device on flywheels. lap it on, nut up tight, they stay there.......

Duzel Solderflux (acid) in the taper helps too, the rust created by the flux expands and locks the tapers together.

[speedpro]

I have used Loctite bearing mount on the taper of a rough corroded crank. Bit of a bastard to get apart but never came off by itself.

I've seen GSX1100 generator rotors win the race to the end of Pukekohe's front straight.

[Frits Overmars]

The first Rotax tandemtwin engines (I received the first two in December 1980) had long tapers on the crankshafts and in the large primary coupling gears. In addition Rotax seemed to have used the strongest Loctite available on those tapers. In trying to get the gears off their tapers I broke two pulley pullers, without joy. I had to heat the gears to such an extent that I had to bin the oil seals afterwards.
One of the many mistakes in those first tandemtwins was that the oil seals ran not on the crankshafts, but on bushes on the gears. This allowed air to leak through the key slots in the tapers, causing all kinds of nasties.
Lessons learned: never use Loctite on tapers if you ever plan to take them apart again; just grind them with abrasive valve paste if they are not a perfect fit. And look for air leaks in even the most improbable places.