R&D platform

[NobleHops]

Awww, Bob, I am so sorry to hear that you’re still there. Keep your chin up and heal up. Pulling for your recovery.

[Rick Pope]

We're here for you Bob. Holler if you need something, within reason.....

[Larry Zimmer]

Keep the good fight going, Bob. We all are looking forward to the day to have you back in the saddle. And, the 'lab'!

[Crazy Canuck]

Sorry to hear you're still laid up in the hospital Bob, the few times I've spent there it felt like jail to me.... hope you get well soon!
I usually pop in to this thread every so often to see if you've told another story....hoping you'll add something soon

[jt]

Bobcat, hope you get feeling better real soon !!!!

[Syscrush]

When "no amputations" is the good news, things sound pretty serious. I think of you a lot, Bob, and hope you're able to pull through this whole mess in good spirits.

[bobcat]

If only the staff(staph) here was half as kind as you guys this miserable experience
might be easier to tolerate. I REALLY miss working (play) and I can hardly wait to get back
to the R&D experimental base and develop some of the ideas I had in mind. It's like a dream
I keep having here where I get out of bed and just start walking around with no pain.
Waking up is tough.
There's so much to do on the project bike that I can hardly wait to get started on, not to
mention rebuilding the motor on my vintage Acura and the list keeps growing.
More dreams to wake up from to reality ?

I guess I should be thankful to wake up regardless the reality and have the opportunity
to change it.

[bobcat]

Onward to more motor relevant stuff. I was talking with Dave Rash a while back about
cam chains and stretch and he said he went one step more to account for actual running
conditions by heating the A chain with a heat gun. When he checked the timing he found
2 deg. more stretch so he reset the timing he wanted to account for it and began to get
the dyno results he had expected.
I don't think I would want to advance my cam timing that much for a street bike (his motors
were being developed for Daytona) but actual running conditions had crossed my mind.

I also had some observations on chain hinge pin size if it hasn't already been discussed here in
another thread. I haven't found anything about it.

[bobcat]

The reduced hinge pin size in the newer cam chains actually makes the chain stronger. !
I have never seen a cam chain break a hinge pin but almost always it's the plates that break
at the pin hole, the weakest part of the chain. The reduced pin size allows for more plate
surface area around the pin. It should also reduce stretch.

[Syscrush]

That's very interesting about strength.

I would think that "stretch" would be worse, though - as it's not really caused by stretching of the plates but by the pin wearing into them and elongating the holes - and a smaller pin would cause more pressure and presumably more wear.

[bobcat]

Hi Phil, if pin hole wear/elongation was the source of stretch, the stretch would be worse with mileage
increase. Since stretch is greater in the first few thousand miles I believe there has to be some plate metal
stretch that the new metal undergoes in the initial heat/cool/tension cycles before the seasoned metal
becomes more stable. I'm sure pin hole elongation is part of the picture though.

Consider what cryotreating does to the grain of the metal. The metal becomes more stable. Although it's
not cryotreating, I would think the heat/cool cycles along with pulling load on the chain would accomplish
something similar.

Maybe laying in this hospital bed has given me too much time to think.
It would be interesting to try a cryotreated A chain. The B chain isn't a problem since it only works against
the force of 12 valve springs. The A chain has to pull against all 24.

[bobcat]

Sorry to hear you're still laid up in the hospital Bob, the few times I've spent there it felt like jail to me.... hope you get well soon!
I usually pop in to this thread every so often to see if you've told another story....hoping you'll add something soon

Forrest, see "story book" in no redeeming value. There's a couple of new ones there.

[bobcat]

I was watching a video about exh. cam duration (automotive) and these guys kept increasing
the duration and gaining HP with each increase without finding a falling off point.
The question I had after watching was what it did to low end and midrange torque ?
All they addressed was peak HP. It was interesting anyway. It's a matter of how you want
the motor to run, what's the most useful power you want.

[bobcat]

The reduced hinge pin size in the newer cam chains actually makes the chain stronger. !
I have never seen a cam chain break a hinge pin but almost always it's the plates that break
at the pin hole, the weakest part of the chain. The reduced pin size allows for more plate
surface area around the pin. It should also reduce stretch.

Note; the pin doesn't contact the sprockets like the old roller style chain thus the only stress
on the pins is from the pull/push of the plates.

[Crazy Canuck]

I didn’t see your post Bob ( been busy getting ready to move) but I’ll take some time to do some reading