i need a place to buy a new set of stroker plates that go under cylinder to adjust for stroke. I've got a cracked one

 

S&S or Truett & Osborn last place I bought any , make a phone call don't rely on their web sites .

http://www.truettandosborn.com/

 

Go to the AHDRA website and look through their online swap meet. There are a lot of folks there that still run old stuff on the strip. If Kirby drops in, he may have a set laying around. I had a set of 1/4" plates but recently gave them away.

 

you can also take the base gaskets and trace them onto the thickness needed and have someone make them.. i have made cylinder inserts to fit into blocks that were bored for bigger cylinders when people would buy a set at a swap meet and wanted stock cylinders-- simple to do they fit the cylinder and are interference fit.. never had one move yet..

 

I understand you just want to replace an existing cylinder spacer plate that is cracked, but I have a question about the theory of stroking that motor.
I hope u find a set. You might consider removing the good plate and using it as a template to have a few more machined. After being scanned into a cnc, the plate could easily be interpolated to fit the other cylinder.

I've got a basic engine design theory question though...
Why would anyone want to increase the stroke of an engine that is seriously undersquare to begin with?

I'm new to Harley's so this may be a stupid newbie question but I have to ask. What is the point? Whats the objective? What are u trying to accomplish by stroking that motor?
More HP? More torque? More displacement?

Any increase in displacement, and horsepower, could be gained fourfold by increasing the bore. At a quarter of the price.
Any increase of stroke will actually degrade performance as TPV is surely encountered in that design.
Not to mention seriously inhibiting service life....
The motor will sound louder, much louder, which some might attribute to power increase, but it will actually have lower performance specs than stock when objectively viewed on a dyno chart.
In other words, you will lose torque once you have passed that curve peak.


Ive been riding bikes for over 40 years, am a mechanical engineer, and have been designing custom engines for over 20. I'm no dummy but I don't get it.

Like I said, it may be a stupid question....maybe I'm missing something, but I'm curious....

Any ideas?
Thanks

 

Years ago unlike today bigger bore kit's weren't available , you want more HP & inches it was longer throw on the rods . Things have come a very long way since stroker plates where common , they where falling out of use in the late 70's for the average guy .

 

2 of the best engines i ever built were #1 using trock cylinders 3 13/16 and at the time a never heard of 4.375 stroke it made a 100" engine then ron trock would ask what C.R. you wanted and the cylinders were made to order.. with these an engine of 8:1-- a sifton 468+ or if and i mean IF you could find the #1+ sifton it was a 436 lift and hyd. the 468S and the 468+ were not noisy tick-tick solid cams as they had ramps for being solid lift cams.... the #2 was a stroke of 3 13/16 and a bore of the same. it made 87" really smooth engine but needed an andrews "M" to make it run and it was a 590 lift really high.. this thing rpm'ed like a jap bike.

harley's respond well to larger bore as the intake valves are to big to begin with.. i always when i had flywheels made i kept the stock weight the lighter flywheels robbed torque. trock set ups were a real drag as they came unfinished and the forged pistons needed a .010 clearance. they lasted alot longer than a stock cast piston only because the ductile iron cylinder was super strong. a normal forged piston like the S&S didnt.. old days it was cut the piston skirt stroker plated plug the oil drains and lower the oil return holes... a 4.250 stroke is ALMOST stock like with cast pistons. i like the sifton cams (when you can find them) as the andrews and others use high lift. the old sifton 414 was the best for an 80" .400 lift but lots of duration.. the 412 was in most bikes. 84 to 88 i used the 468S ... a good heavy bike sifton was the old 55Q 410 lift closed up timing made for low end power and it was hyd.. i run the leinweber L3S -- THE most for power but NOISY...

 

Still a have Sifton 486S tucked away , I'm a big fan of the V-Thunder cams and Jims hyd. lifters for street use shovels up to 96" I've had very good results with them in 88" & 93" daily riders over the years . Andrews and I never have got along well , one to many new out of the box 15 or more degree's out on the timing and the power band sucks till 2500rpm or more .

Leinweber makes good stuff but their ramp design is noisy and has taken a lot of lifter out .

 

we used dyno cams in our racing karts-- the 95-3 was a fast ramp cam and it would(did) bust lifters and the lifter boss.. i have good luck with the leinwebers.. probably due to the use of the ultima oil and the militec 1 additive.. yeah the andrews flat out run out of power.. those are constant velocity cams made for manifold vacuume.. the andrews "M" was a 264 duration but 590 lift needed triple springs and the most inner spring would brake from time to time.. but because of the timing events and the short stroke it worked better than other cams. kinda like the old 61" cams they were designed for the 3.500 stroke a FLH cam didnt work as it should... a trock 3 7/8ths cylinder with the 3.500 stroke gave a 82" displacement .. these i used the sifton #1 not #1+ just the #1 it was 28/62 270 duration and a .436 lift intake --- 50/18 248 duration and .436 lift -- hyd lifters. this cam worked well with this.. the short stroke made the engine live and super smooooth,but had more power than at the time the new 80" shovel. it was more of a low end to upper mid range.. but on the highway it was a dream to ride as it was smooooth... its had a really weird exhaust noise kinda like the old bsa's and a idle like one aso with that thump-thump-thump at a red light... cant find those cams to save my life...

 

Biggest bitch I had with Sifton before they went under was soft lobes chewing themselves up , got a " C " Andrews out in stash somewhere too . When I could buy wholesale I went through a bunch of cams finding the sweet spot for the 88" & 93 " daily driver shovels , settled on the V-thunders now good pull right off idle and ground for hyd. lifters even stock respond well to them . Do have to get the springs set up right but don't need triples I always seem to break the inner with those . My Leinweber hands on is limited aside from a few come through with the noise bugging owners .

Check the specs on the V-Thunder SHV 4040 , 4050 , the last one has that exhaust characteristic your talking about , bugs the **** out the twinkie crew around here they can't get theirs to idle like that