Auto Advance Distributors and left handgrip control

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EasyDuz'er
Posts: 14
Joined: Sat Nov 20, 2004 7:06 pm
Location: Florida

Auto Advance Distributors and left handgrip control

#1

Post by EasyDuz'er » Thu Jan 13, 2005 7:33 pm

For purposes of building a dependable replica, early 50 pan, whats the best way to go with regard to distributors. Stick to the orignal mechanical advance in which case I guess you have spirals in the left hand grip for spark advance or is it best to go with an auto advance distributor. If you go with an auto advance distributor what do you do with the left hand grip and spirals?

If I use the mechanical advance, how often do I utilize the manual advance hand grip control, only when starting the bike? or more?

Take it,

EZ



Cotten
Posts: 6791
Joined: Mon Aug 26, 2002 9:09 am
Location: Central Illinois

#2

Post by Cotten » Fri Jan 14, 2005 3:42 am

Mechanical advances are quite dependable.: No springs or centrifugal weights to wear out.

Many repop autoadvances use chubble points cams, which technically aren't as appropriate as the dwell profile on your mechanical. And the spring tension is not the same as a '65's either. But they seem to function OK.

If you decide to run an autoadvance, you take all of the mechanical hardware, and safely stow it away for later.

You only need to retard for starting. Retarding on hills is greatly overated.

...Cotten

VT

#3

Post by VT » Sun Jan 23, 2005 2:30 pm

The re-pop manual advance circuit breakers are okay. Their made by the same people in China that make V-Twins auto-advance and have a proven track record. I own one. The spiral for the spark is the same spiral that's used on the throttle. Same part number, same part, same function. The spirals push the control cable. If you run a Bendix, it requires a "pull" spiral for the throttle only. They have those at V-Twin as well. It's the spiral for the old "Hummer".
In my opinion, if you want the most crowd-bang for your buck, you'll run a manual advance. Number one, it's a crowd pleaser to see you twist the left throttle prior to starting the machine. Number two it's a theft deterrent as most people do not know how a manual works, much less the concept of a "kick-starter". They do know what a "key" is, and that when you turn a "key" the motor magically comes to life. But as far as putting your foot (how can you start a motorcycle with your.... foot?) on a pedal and pushing it down a short distance with very little effort, oh man, that act alone just destroys brain cells with the public. Just leaves them speechless. 99% of the "people" will ask you....."Is that an Indian?". So yeah, if you want to go around putting people into an instant mid-life crisis and draw crowds with people asking you alot of the same questions....go ahead on......hook up with a manual advance. But I warned you. 8)
I'll go snap a pix of the Taiwan job and let you judge for yourself.

EasyDuz'er
Posts: 14
Joined: Sat Nov 20, 2004 7:06 pm
Location: Florida

V-twin Replica vs. STD Head and S&S case motors

#4

Post by EasyDuz'er » Mon Jan 24, 2005 12:01 am

Vintage Twin. Thanks for the info. Ok, so far the advice has been go with the mechanical advance distributor and go with the stock exhaust port heads. The RoadRatRoberts web site says you should go with the STD motor due to automatic advance, 3 bolt exhaust flange and better oil pressure. He claims 30 psi at idle versus 8 psi for stock. RoadRat says the exhaust pipe headers will constantly pop off the stock heads and you won't get proper lubrication with the stock motor. What do you think? I think you said you have the STD motor but you recommend the V-twin replica motor. Why did you not go with the replica motor on the two bikes you are buiding?

Take it,

EZ

en the STD Head / S&S Case motor and the V-Twin Replica Motor.

VT

#5

Post by VT » Mon Jan 24, 2005 3:48 am

I don't like three-bolt (Shovel) flange. Can't get exhaust headers for swing arm, only rigid. I like spigot exhaust and Linkert intake. I don't like the flatten-side, Evo look of the STD heads vs. the nice eliptical OEM cylinder heads. Check it out for yourself. Look for the flattened fin profile on a set of STD heads. It's all from inside Lou Tractenburg's vision of a Pan motor. He designed the crankcase from a '69 motor and the Shovel intake Pan heads had "better flow than original". His words. We featured an STD motor in the first book, because in 2000 only STD made Pan heads or crankcases. I didn't even realize the crankcase didn't have a relay boss until the heads were installed. I freakin' flipped-OUT! (I guess I would have built the motor anyway, but I put an OEM timer in it that I can't get out now unless I pull the STD heads!) That's why the "weld-on" relay boss accessory is pictured on the same page as the motor!
S&S's motors use Allen head cam cover screws and their crankcase didn't come on line until just before publishing. It all comes down to this with me: What's the most affordable, replica, 74 cu. in. motor available, without sacrificing quality, where a quality part(s) is of paramount necessity, but then, having a motor that's real hard to tell from OEM?
S&S crankcase's w/ a four-finned cam cover on a Knuckle bottom end? Not for me, but that's just me. Most people wouldn't know the difference.
Last edited by VT on Mon Jan 24, 2005 10:16 pm, edited 2 times in total.

VT

#6

Post by VT » Mon Jan 24, 2005 5:58 pm

If you like the three-bolt exhaust, you may want to consider buying the Pan motor Stett built. I will ask him to change out the manual circuit breaker for an auto-advance. The motor has OE cylinders, crank pin, countersunk hex-screws in JIMS polished tappet blocks. Bendix carb. Ready to drop in a frame. $8,000. plus shipping. You can find cheaper motors, but this is a Stett motor, with hand picked parts. S&S/JIMS rods and shafts. Wiseco pistons. 74". I've never laid a wrench on it. All receipts included.
I'm ordering a '41-49 V-Twin oil pump (12-1947), for the knuckle motor to complete a chapter.
The '50-67 pump bodies (VT 12-9931) look the same as the '41-49. Only the end caps are different. Not interchangable with OE oil pump parts. Selling the S&S pump that's on it now. Never used.

EasyDuz'er
Posts: 14
Joined: Sat Nov 20, 2004 7:06 pm
Location: Florida

#7

Post by EasyDuz'er » Tue Jan 25, 2005 2:23 am

Ok. So I am convinced on the V-Twin replica motor. I too like the original look, I was just concerned about quality and reliability issues, mainly from what I read on the RoadRatRoberts website.

You mentioned the relay boss on the vtwin replica motor. I went back and looked at the case details and I read what your talking about. Great point. Thanks.

You mentioned the four fin cam covers. I was wondering about that too. The photo of the vtwin replica motor also shows a four fin cover in lieu of the eight fin. The only place I see the 8 fin covers in on the pages for purchasing the covers separately. Does the replica motor come with the 4 fin as shown in the photo or can you get it with the 8 fin without having to purchase the 8 fin cover separately?

If I have to buy an 8 fin cover separately, the book says the covers have to be reemed for final fit. What does cam cover reeming involve and is that something that only an experienced mechanic or machine shop can do?

Thanks

EZ

VT

#8

Post by VT » Tue Jan 25, 2005 4:02 am

8-fin Knuckle, up to and including, '53 Pan.
Four-fin for '54 to 64. Don't try and build your own motor. Buy a motor complete, replica USA/Taiwan or total USA. Whatever, just don't build it yourself, or you'll never get one of these on the road. There's alot to building your own, especially your first one, turn signals, etc. It best to have another Big Twin to ride while your building one of these. I haven't had my Pan running since June of '03 and it's a very in-complete feeling.

Panama

#9

Post by Panama » Thu Feb 03, 2005 8:34 am

It's not really a deal, if it's taiwan (read crap)
S&S & Others in the USA have great reputations for their quality.

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