solid lifter using pushrod from hyd set-up

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RooDog
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Re: solid lifter using pushrod from hyd set-up

#16

Post by RooDog »

I should note that I did have to loosen the rear cylinder head bolts to slip the intake pushrod into place which I wasn't real comfortable with and have retorqued the bolts twice now. Thanks for all the input while I pondered the idea of switching to the solids.
[/quote]


Something ain't right here. Colony PRs typically have only one long PR, it goes in the front exhaust. If there is another long'ish rod, it goes rear Ex, and the shortest ones are for the intakes


A hot motor should start with little or no throttle, 1/2 T sounds like too much to me. Retard as needed to avoid kick back. It should be a one/two kicker when warm/hot...
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Sarre
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Re: solid lifter using pushrod from hyd set-up

#17

Post by Sarre »

PanheadBob58 wrote: Tue Jul 27, 2021 3:03 pm I haven't perfected my hot engine starting procedure yet and would like some input from others on how they approach their starting procedure while hot. Staring the bike cold is no problem at all just the hot start condition, I seem to want to retard the ignition even while starting hot and holding the throttle half open with no prime kicks or choke used (carb is a Linkert). And it seems to take quite a few kicks and adjusting this and that to get it to fire hot, so what do you guys do to start your Pans hot?
awander wrote: Tue Jul 27, 2021 3:56 pm My hot-start procedure (war-start, too) is to retard the ignition, turn on the switch, open the throttle all the way and kick it. It almost always starts on the first kick that way. Sometimes the 2nd.
As @RooDog already mentioned, also in my opinion something is wrong if you need the throttle that far open for starting up. If the engine is hot and you park it, heat will dissipate towards the carb, thats why insulator blocks are placed between the intake and the carb. Also if the fuel line is running between the two cylinders it is a good thing to have a heat resistant insulator around that line. However, such an insulator will retard heat but radiating heat from the cilinders will still heat up the intake tract and possibly the carb. Therefore it is good to flush the intake with fresh air (fuel mixture), with the ignition off, it should start first kick (imo) after that flush. I always open the throttle all the way when hot, kick it once or twice without ignition and then start it like normal. If the engine starts, and a few secs later, or just when you hit the throttle to take off, suddenly dies, fuel in the fuel line is possibly boiling resulting in gas in the line.
PanheadBob58 wrote: Tue Jul 27, 2021 3:03 pm The associated mechanical tappet noise that comes with running solid tappets is not bad at all, and as I've read in at least one post on this site, there seems to be a typical pattern of parts adjusting to the total engine temperature, which would be a no noise situation at cold and then becoming a little noisy while the engine is approaching normal operating temps and then it all settles down to a very mild tapping noise when everything approaches normal engine operating temperature.
I agree, and thats exactly my experience.
RooDog
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Re: solid lifter using pushrod from hyd set-up

#18

Post by RooDog »

Just something to think about:
If an engine, any engine, will run at idle with the throttle closed, and is properly tuned, why would it not start hot, with the throttle closed, in the idle position?
Just food for thought.....
....RooDog....
FL54
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Re: solid lifter using pushrod from hyd set-up

#19

Post by FL54 »

PanheadBob58 wrote: Tue Jul 27, 2021 3:03 pm Well it's been approx. 5 weeks since replacing my hydraulic tappets with the Jim's adjustable solid tappets and I used the Colony aluminum pushrods 7122-4. I'm pleased with the fact I can now ride the bike longer without worrying about when the extreme tapping would show up. The associated mechanical tappet noise that comes with running solid tappets is not bad at all, and as I've read in at least one post on this site, there seems to be a typical pattern of parts adjusting to the total engine temperature, which would be a no noise situation at cold and then becoming a little noisy while the engine is approaching normal operating temps and then it all settles down to a very mild tapping noise when everything approaches normal engine operating temperature. I haven't perfected my hot engine starting procedure yet and would like some input from others on how they approach their starting procedure while hot. Staring the bike cold is no problem at all just the hot start condition, I seem to want to retard the ignition even while starting hot and holding the throttle half open with no prime kicks or choke used (carb is a Linkert). And it seems to take quite a few kicks and adjusting this and that to get it to fire hot, so what do you guys do to start your Pans hot?

I should note that I did have to loosen the rear cylinder head bolts to slip the intake pushrod into place which I wasn't real comfortable with and have retorqued the bolts twice now. Thanks for all the input while I pondered the idea of switching to the solids.
At the risk of contradicting Andy, my hot start procedure is to retard the timer about a third and no throttle. Usually starts first kick. All these old bikes have their own idiosyncrasies.
kitabel
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Re: solid lifter using pushrod from hyd set-up

#20

Post by kitabel »

When examining tappet rollers, when rotated by hand it should be smooth, have (nearly) zero resistance, and no "scratchy" spots. That may be a bad needle, or just a bit of gasket, but it's not safe. If you rotate it in a parts washer stream: is the washer's filter really small? You may be adding debris.
'Any shake is fatal.

Unless it's way off, lash beyond correct (looser) has almost no effect on starting. The CCP may move slightly, harmless.
Too tight? That cylinder won't run.
An engine that drops a cylinder at speed when really hot, but recovers after it cools down, may be a tight pushrod (2nd choice: seizure). Don't ride it like that!

My OCD has made me burn my fingers many times confirming an adjustment as safe: when up to full temperature the pushrods will roll between your fingers but not shake side-to-side.
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Re: solid lifter using pushrod from hyd set-up

#21

Post by awander »

kitabel wrote: Wed Jul 28, 2021 9:07 pm ...Unless it's way off, lash beyond correct (looser) has almost no effect on starting. The CCP may move slightly, harmless....
CCP?
kitabel
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Re: solid lifter using pushrod from hyd set-up

#22

Post by kitabel »

"Cranking cylinder pressure", what shows on a gauge.
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