Sport Scout stroker project

tprjj49707,
Crank pin is the same Chief or Scout
For the pinion you need either a stepped Stroker pinion Stark has these that bolt right in Kiwi and Ziggy have one that takes a special race. Or a taper adapter Chuck Miles has these.
Sprocket shaft is regular Sport Scout
If you want to be alot more bullet prof Rocky has a steped crank pin so that you can use Sportster Rods.
Dusty

tprjj49707,
If your rods measure 7.5, better back up and get the right ones first before you start balancing. Scout are 7.440 and if talking performance you can't be guessing about decimal points?
?????
1957S/VG

Try picking up and reading "One Good Run" for info. There are copies of some pages of his note book floating around. Most manuals cover stock engines and if building a stroker, its all custom
?????
1957S/VG

7.44?

Source is?

reading through all the posts for stroking a scout it appears many would like to do it we just need a good starting formula am i correct that the advantages are to install chief flywheels with hd sportster rod assy are the pistons custom made in this application also which cam spec will be the most benefit to this considering that most of these bikes are to be ridden on the street is the upgrade to the sportster assy really cost effective if one were a burt munro there is little doubt however most of the riding i do on my hd is putting with occasional bursts of speed are the ss rod assy's really that delicate that they are unlikely to survive the additional stress of a 57in or as i read the possibility of a 64in scout i am preparing to start building my engine so i would prefer to buy parts only once thanks to all who use this forum it is enlightening

I don't know if any Scout stroker pistons are available, if yes this makes the remaining choices easier as to economics: calculate what you need to get the dome to a good quench distance: piston CD + rod length + 1/2 new stroke should equal stock piston CD + 9.152" (stock 7.402" rod length + 1/2 stock 3.5" stroke).
If not, finding a piston is IMHO far the most important thing to do especially since not all engines will have the same shape - pop-up for Bonneville, etc.
The Truett wheels will probably be Chief (4.4375" = Scout + 15/16") stroke, use Sportster pin, and need a small base shim to get the stock distance back but this is not fixed yet, perhaps reducing the stroke to 4.402" to get the exact total height would be easier for most people. The reason for the XL rod is simple: all new stronger parts cheaper than rebuilding the original worn 60 year old parts.

The Chief isn't the upper limit of stroke length, but the rod angle is getting a bit too sharp for long use (still better than a KH). Wih the XL rod 4.625" works well as to angle, but this will cost $$ since Truett has to make it special, or you could use an existing S&S Sportster product (common size) and adapt the shaft tapers.

I'm happy to report that Paul Osborn has received the sample Scout flywheels generously loaned by Dusty-Dave, and has already begun taking measurements and preparing to make molds.

I have new pistons in stock for stroker scouts.
Rocky
1957S/VG

Excellent, do they give stock deck clearance with Chief wheels and Scout rods?

Yes , stock deck clearance, with chief wheels and scout rods or XL rods can be used as they are somewhat beefier than the scout rods. The XL rods come in handy for short bursts of speed to test your stroker or to impress your buddies. Altough the XL rods require our special crank pin to fit the chief wheels. Bonneville heads are a plus or stock heads can be opened up.
Any of the aftermarket cams, including east coast historical grinds, ie, Murdaugh, Clay Smith etc. will work fine. We offer a few different choices

Now I'm confused.
Which dome design are your pistons?

All 1952-85 same at 7.4375"
XR1000 & Evo 6.926"
S&S #7900 7.113"
Buell XB9 7.27"
Carrillo 7.80"
Really late rods take .792 pin.

The pins were designed around the 57- mid 80's XL rods as these were common enough and stronger than the spindly Indian rods. Which is insurance for occasionally bursts of abuse. Keep in mind, in funds are abundant, they please look at other more expensive options, KR, XLR or titanium or whatever suits you

this has been most helpful so far as to the planning it seems as there may be a sufficient number of potential strokers to give all interested a good start toward a reliable performance upgrade i hope at some time i will be able to contribute more technically is there any info to guide as to porting/relieving with the stroker increase or is benefit not labor or cost effective thanks for the help

XL cages.
XL pin is std. H-D size at .791" and larger than Scout at .750" so a new bushing with a thicker wall may help.

Panic is correct about rod bushings which are supplied with the pin. You will need to PM me at ironwigwam.com for prices. Stock XL cages are used as are the rollers. Depending on the fit of taper to wheels, there will be some shimming needed using Indian thrust shims.
Rick

Rocky,

Was is the prevailing wisdom on replacing the cam follower shafts?

Do they go in back to front ? front to back?

Heat and press?

I really don't want to screw this up.

jj

JJ,
The cases need to be split and the shafts are pressed out from the inside. You need to have the surrounding area around shaft supported before pressing out.
You need to hone the rockers to find the size shaft you need.
Installation is the reverse.
Rocky
1957S/VG