HarleyTechTalk

Technical Forums => Twin Cam => Topic started by: Raleigh111 on September 25, 2021, 07:21:25 PM

Title: 103 crank .008
Post by: Raleigh111 on September 25, 2021, 07:21:25 PM
Whats then consensus now. Tearing mine down, 50k mile rebuilding  with 110 cylinders .008 is where she is at.??
Title: Re: 103 crank .008
Post by: Raleigh111 on September 25, 2021, 07:23:16 PM
Here you go
Title: Re: 103 crank .008
Post by: Ohio HD on September 25, 2021, 07:30:07 PM
I think a lot has to do with what you intend to use the motor for. Just riding it, or running it hard. And I assume it's a hopped up build now?

A stock motor just ridden around normally, the crank is probably where it is for life. Running it hard, may stay there, and it may not. Your not all that far away from sliding a new Darkhorse crank in that'll stay straight for ever. Or send yours to them, they can fix it and it'll stay fixed.   
Title: Re: 103 crank .008
Post by: FXDBI on September 25, 2021, 08:57:59 PM
Any sticky spots in the rods turning it over several times?  With .008 its got to have a buzz to it now in the upper revs.  Bob
Title: Re: 103 crank .008
Post by: Ohio HD on September 25, 2021, 09:10:03 PM
I doubt there's any feeling from the run out. That's an 'A' motor, so it's rubber mounted.
Title: Re: 103 crank .008
Post by: FXDBI on September 25, 2021, 09:26:46 PM
Quote from: Ohio HD on September 25, 2021, 09:10:03 PM
I doubt there's any feeling from the run out. That's an 'A' motor, so it's rubber mounted.

My Dyna @ .006 would put my feet to sleep from the buzz. New crank is under .001 and my feet are fine now.    :scratch:   Bob
Title: Re: 103 crank .008
Post by: Raleigh111 on September 25, 2021, 09:33:23 PM
I dont feel nothing more then normal, I have done more burnouts more then i care to admit. I Wish i new if it moved from stock or is this just where it was from day one? Guess i will not know the answer to that. Looking for excuse to build to 124 - 126? If it will last as a 110 for another 30-40k miles i would be okay.
Title: Re: 103 crank .008
Post by: Ohio HD on September 25, 2021, 09:38:22 PM
Quote from: FXDBI on September 25, 2021, 09:26:46 PM
Quote from: Ohio HD on September 25, 2021, 09:10:03 PM
I doubt there's any feeling from the run out. That's an 'A' motor, so it's rubber mounted.

My Dyna @ .006 would put my feet to sleep from the buzz. New crank is under .001 and my feet are fine now.    :scratch:   Bob

You have sensitive feet.    :teeth:
I've ridden bike as far out as 0.009", it couldn't be felt. Ws just found when replacing chain tensioners.

Right or wrong HD has the maximum spec. for crank runout set at 0.010" checked in the cases.
Title: Re: 103 crank .008
Post by: Raleigh111 on September 25, 2021, 09:40:33 PM
Quote from: Ohio HD on September 25, 2021, 07:30:07 PM
Darkhorse crank in that'll stay straight for ever.
You are a bad influence
Title: Re: 103 crank .008
Post by: Ohio HD on September 25, 2021, 09:46:53 PM
Quote from: Raleigh111 on September 25, 2021, 09:40:33 PM
Quote from: Ohio HD on September 25, 2021, 07:30:07 PM
Darkhorse crank in that'll stay straight for ever.
You are a bad influence

This is probably true.    :teeth:
Title: Re: 103 crank .008
Post by: kd on September 26, 2021, 05:44:11 AM
Quote from: Raleigh111 on September 25, 2021, 09:33:23 PM
I dont feel nothing more then normal, I have done more burnouts more then i care to admit. I Wish i new if it moved from stock or is this just where it was from day one? Guess i will not know the answer to that. Looking for excuse to build to 124 - 126? If it will last as a 110 for another 30-40k miles i would be okay.

I would guess if you look at the costs between a 110 build and that 124 you get wood over they are close enough that you should just go 124.  MANY members have said they should have because that's likely ethers you are going and then you'll have to respond all that cash over again.
Title: Re: 103 crank .008
Post by: PoorUB on September 26, 2021, 09:09:42 AM
Quote from: Raleigh111 on September 25, 2021, 07:21:25 PM
Whats then consensus now. Tearing mine down, 50k mile rebuilding  with 110 cylinders .008 is where she is at.??

Are you going to keep it for a few years? Fix it and trade it off next year?

If were mine and I planned on keeping it and was knowing to beat on it a bit I would get the crank rebuilt or toss in a S&S. If you figure you will sell it in a year or two, run it.
Title: Re: 103 crank .008
Post by: mike jesse on September 26, 2021, 09:25:22 AM
.008 in. TIR is outside of my comfort zone unless it's going to stay just the way it is.
If money is tight, leave it alone.
I would vote to send it out to Darkhorse for a rebuild with new full width rods/bearings.
Title: Re: 103 crank .008
Post by: jsachs1 on September 26, 2021, 02:39:28 PM
Here's some food for thought. I was doing a build on a late model TC engine (30,000 mi.), and in checking the flywheels, I found pinion runout of .010". Checked, and tripled checked at the pinion shaft , while assembled. Removed engine, complete disassembly. :banghead: Put the wheels between centers in my lathe, about a week or so later, 2 dial indicators (1 on the motor sprocket side, other on the pinion shaft). readings = PINION - .0015",  MOTOR SPROCKET SIDE = .003". Checked that deal 4 or 5 times. Consistent readings.
I talked to Darkhorse, and they said they have seen that at times. Go figure. I put a new set of S&S wheels in that engine, with 2 lefty bearings, and readings were good. You just never know. :cry:
John
Title: Re: 103 crank .008
Post by: Raleigh111 on September 26, 2021, 06:13:27 PM
Quote from: jsachs1 on September 26, 2021, 02:39:28 PM
Here's some food for thought. I was doing a build on a late model TC engine (30,000 mi.), and in checking the flywheels, I found pinion runout of .010". Checked, and tripled checked at the pinion shaft , while assembled. Removed engine, complete disassembly. :banghead: Put the wheels between centers in my lathe, about a week or so later, 2 dial indicators (1 on the motor sprocket side, other on the pinion shaft). readings = PINION - .0015",  MOTOR SPROCKET SIDE = .003". Checked that deal 4 or 5 times. Consistent readings.
I talked to Darkhorse, and they said they have seen that at times. Go figure. I put a new set of S&S wheels in that engine, with 2 lefty bearings, and readings were good. You just never know. :cry:
John
That is interesting
Title: Re: 103 crank .008
Post by: Admiral Akbar on September 27, 2021, 11:12:52 AM
Quote from: jsachs1 on September 26, 2021, 02:39:28 PM
Here's some food for thought. I was doing a build on a late model TC engine (30,000 mi.), and in checking the flywheels, I found pinion runout of .010". Checked, and tripled checked at the pinion shaft , while assembled. Removed engine, complete disassembly. :banghead: Put the wheels between centers in my lathe, about a week or so later, 2 dial indicators (1 on the motor sprocket side, other on the pinion shaft). readings = PINION - .0015",  MOTOR SPROCKET SIDE = .003". Checked that deal 4 or 5 times. Consistent readings.
I talked to Darkhorse, and they said they have seen that at times. Go figure. I put a new set of S&S wheels in that engine, with 2 lefty bearings, and readings were good. You just never know. :cry:
John

John,
Did you check the runout on the center holes?
Title: Re: 103 crank .008
Post by: Raleigh111 on September 27, 2021, 11:26:49 AM
My mom warned me about friends like these on this websites! She said to stay away. Stay tuned. Glad to see max around I love picking his brain and others! Got a bunch of fresh 110 stuff if any one has 124 stuff.
Title: Re: 103 crank .008
Post by: Raleigh111 on September 27, 2021, 11:28:19 AM
Got a call in to bvbob. I think he knows where to get sns parts. :teeth:
Title: Re: 103 crank .008
Post by: jsachs1 on September 27, 2021, 01:17:20 PM
Quote from: Admiral Akbar on September 27, 2021, 11:12:52 AM
Quote from: jsachs1 on September 26, 2021, 02:39:28 PM
Here's some food for thought. I was doing a build on a late model TC engine (30,000 mi.), and in checking the flywheels, I found pinion runout of .010". Checked, and tripled checked at the pinion shaft , while assembled. Removed engine, complete disassembly. :banghead: Put the wheels between centers in my lathe, about a week or so later, 2 dial indicators (1 on the motor sprocket side, other on the pinion shaft). readings = PINION - .0015",  MOTOR SPROCKET SIDE = .003". Checked that deal 4 or 5 times. Consistent readings.
I talked to Darkhorse, and they said they have seen that at times. Go figure. I put a new set of S&S wheels in that engine, with 2 lefty bearings, and readings were good. You j

Did you check the runout on the center holes?

S&S dialed in .0015" X .0015"
John,
Title: Re: 103 crank .008
Post by: OldBogie on September 27, 2021, 04:57:18 PM
Harley spec at pull and check both sides is .005 on the cam side, you can expect the drive side is 3 to 5 times your .008.

In simple language the axles are out of line as in twisted with the flywheels. Thes causes the output shafts at both sides to wobble. The further from the main case bering you go the greater the off center distance becomes.

If your running gear drive cams this will wipe out the drive gears. It will take out the oil pump once the wobble exceeds the clearances as at that point it starts carving the softer aluminum housing thus allowing internal oil leakage if left to proceed eventually the pump jams and hard parts come out.

On the primary drive side an early indicator is the automatic adjuster over tensions the drive you find your self making fixes frequently. This will followed by compensator wear, possibly retention bolt failures will happen before the whole thing goes probably taking the alternator with it.

So left to its own devices it's a lot more than a vibration issue. This eventually leads to destruction of the engine.

At .005 on the cam and pump pinion Harley recommends removal to put the crank on centers to see how bad it is, they would recommend replacement, I would recommend welding. Prior to the twin cam the earlier engines used interference taper fits and keyed ways to align the crank pin with the flywheels then gland nuts to clamp the assembly together. This is a costly process to perform but it is accurate and strong. Radial aircraft engines used this assembly method with great success. However, cost cutting being the modern mantra of American society, Harley decided to use a pressed fit for the crank pin to flywheels. Given the forces involved especially at the hands of guys that like to twist the throttle hard or add cubic inches or other hot rod techniques to increase power you can see where a pressed crank pin can start to cause trouble by allowing slippage in the otherwise unsupported joint that simply depends on friction to stay together.

So there you are, depending on what you want to do to and for how long you want to keep it depends on how you decide to fix it or not.

Bogie

Title: Re: 103 crank .008
Post by: Thermodyne on October 20, 2021, 12:20:54 PM
If I'm that far into it, no way do I move forward with a .008 pinion shaft.

Past that, you need to check the sprocket shaft too.  They will often show .010 or more when the pinions are 005 or 006.  And .010 on the sprocket shaft will hurt you more than 007 or 008 on the pinion.
Title: Re: 103 crank .008
Post by: Don D on October 22, 2021, 07:15:32 AM
So are the centers concentric to the races? Randy told me most are not and the centers need to be reestablished.
Title: Re: 103 crank .008
Post by: kd on October 22, 2021, 01:49:09 PM
That's my understanding too.  I remember it was discussed here some time ago not to trust them being centered.
Title: Re: 103 crank .008
Post by: Don D on October 22, 2021, 01:57:01 PM
They make dedicated machines to do that or it can be done with a CNC mill with the right tooling. The grinders look like a pedestal drill with a cone shaped grinding wheel.