JMC swingarm

[shovelbill]

what's up men?
my question is this. has anyone had any experience with or know anyone that has had a jmc aluminum swingarm for a 4 speed? i understand that the piece is much lighter and a whole lot more rigid than our typical swingarms. if so it's got to enhance the spirited riding experience, with the proper suspension components of course. i should put it another way, when i beat on it will it help with the squirly-ness? i'm looking at works performance shocks and springs with the gold valve emulators by race tech for my ride.  thanks........

     

[randallwhitman]

I can't imagine an aluminum swingarm that would be stiffer than the steel stocker, but I don't have much imagination.  I do have 11" Works shocks on mine......good product, and rebuildable.  A lot of shovel guys like the high end Progressive Suspension shocks.  Put a Sturgis (shovel) swingarm from Paughco on there, and with some other mods, you can run a belt to the wheel.

[76shuvlinoff]

Gotta agree with randall but I also lack imagination. 
With a good set of bearings, torqued properly, and a good set of shocks there shouldn't be much  squirly-ness at all.  The neck needs the same treatment.

[Lew]

JMC makes some killer swingarms that are worlds different than stock.  They can custom make anything you desire....for a price.  I've seen them used on drag bikes that could twist a stock swingarm like a pretzel.  They definitely add that custom touch too....for a price.
Lew   

[shovelbill]

thanks guys for the replies. my '85 evo fx had some shorty progressives after the struts and 15 of the 17 yrs i had my 84 softail i had struts under her too. last 2 i put in some works shocks and really liked them much better than the progressive shocked s/tails ive ridden. my REAL problem is that sometimes i ride these chassis' to the limit, i think they are well tuned (suspension wise) FXRs and probably should just build one of those (shovel powered naturally) for when i really want to get on it. living in nyc will always test a chassis/suspension, and riding the way we do some(most) of the time doesnt help.  this is one of the shovel ones with eccentric adjusters.

[randallwhitman]

I agree with shuvlinoff.....(Isn't that Mark?)......anyway, the four speed frame is a very solid platform.  Try a late model bagger if you don't believe me (NOT the '08 models).  The only limiting factor to handling is the lean angle.   

[shovelbill]

i appreciate the feedback and i agree 100% with 76,  no doubt the 4 speed is ok for what it is. maybe squirlyness wasnt the right word for what i meant. the problem is actually me and the way i ride sometimes. im going to take this platform to the next level from what im used too. i never could afford 2 bikes so i did everything with the ones i had.

the only things i'm keeping from this '80 is the title, frame, and engine cases. everything else will be "new and improved" for this particular bike. when i get most of the stuff together for the roller im going to document the whole ground-up(first for me), maybe ill put it up here if that would be cool. the research and list is done, now im starting to buy things in the order that i need them.

randall, i had the belt setup on my '85 till the second time i broke it. after that all i busted were mainshafts, haha. thanks

[76shuvlinoff]

   Sounds like you ride pretty hard shovelbill.  I gotta add to my post that just about nothing is "bulletproof" ..Especially from the factory.    My comment were based on the way this old fart rides LOL.  That swingarm looks killer. keep us updated on all your upgrades, we all like to tinker.

... Mark

[biker3r]

The hospital sign in the picture cracked me up, looks like a couple of the guys in the pic could use it

[randallwhitman]

If you're going for the really good stuff, get yourself a six speed......you and your motor will love it.     

[shovelbill]

yea 76, sometimes i to play with the jappers, especially light to light.
Biker3r, that was the day after a straight thru run to sturgis in '90, i cant remember what kenny's(RIP) stroked '36 busted but we were pretty shot that day, touring the country on nyc street bikes takes it outa ya. 2 stroked shovels, a '49 pan and my "new fangled" '85 with a street racing motor.
Randall, im going to be using a baker 6 into 4. i dream about it every night!

ill put up a parts list, but check out these goodies i'll be using by Mike Sorensen of Sorensen Performance in Canada .





i can send better pics if anyone want them.......the rollers aint on his website yet. they're octoganal shaped and the backing plates are for the super g & the psi. beautiful stuff. go to his site and check out the heads. http://www.spchoppers.com  he's a really cool dude to talk to and ill be getting my top end from him. gotta call him tomorrow to get the piston weight so i can give it to t&o so i can get my wheels made up.

[randallwhitman]

OF COURSE we want pics!!!!!!!     

[shovelbill]

[shovelbill]

i'll never remember how i did that but you can see these better. took about an hour!

[randallwhitman]

Bill.....what are the round, shiny gizmos that look like they might mount on an SnS carb?   

[shovelbill]

Randall, those are the backing plates he designed to fit the s&s super G and the PSI big air carb(same mounting holes and manifold). they take a  k&n air filter that you would match to your engine's breathing requirements.

[randallwhitman]

Cool......what covers can be used with them?

[bob_e95482]

Not meaning to hijack this thread, but I've looked at those Sorensen roller rockers before. I had seen some prototype Sorensen shovel cylinder heads with squish combustion chambers that took flat top pistons. Know any more about those?

[shovelbill]

hey Bob, no i dont know about those flat tops. about a year or so ago i read an article in american cycle magazine about these prototype heads that he's got on the website. they were going to run another article on a 93" build but for some reason never did. i wasnt in a position to talk to him back then but 3 months ago when i was able to i called him about it and we've had great communication since. all the cad work is now approved and the new prototype billet(not the prototype std castings on his site)will be shipped to him for flow bench testing. should be very soon now. JE is making the pistons to match his combustion chamber shape but these heads will work with a low dome piston as well. i would reccomend anyone to call
Mike and ask about it. he's answered every question i ever came up with, shares his knowlege freely and has no ego like some people i've tried to question about their products. i feel really comfortable about doing business with him. my bros say that i'm the test dummy for this hi-tech shovel i'm building, but i've been called worse by better, haha.
i do believe that Gates Performance Engineering does some kind of hi-squish setup on shovels, i talked to Greg over there and he's a real cool guy to talk to as well.

right now im buying pieces as i need 'em to get this frame on 2 wheels but when the heads are ready and i have the money ill be getting most of my topend from him. i know i've rambled here a bit but i hope this helps ya out.

[FSG]

i'll never remember how i did that but you can see these better. took about an hour!

[shovelbill]

randall, i never asked about what goes on the front of those filters. good question tho, kinda like a Bob Wood setup i would think. i never got to call the other day, when i do ill ask.

[Lew]

i know i've rambled here a bit but i hope this helps ya out.


Bill...please continue to ramble!  I'm sure others feel as I do and would like you to keep us posted on all aspects of your build.  Thanks for sharing! 
Lew

[shovelbill]

here ya go,
asked a few questions got my answers and pulled the trigger on the swingarm. basically a shovelhead swingarm with a dyna brake setup with the stock lug in case i want to go back to stock style. expensive as all hell but for once in my life i'm not building on a diet. black powdercoat, 45 mm axle adjusters. here is the answer from top fuel tech, takes 8-12 weeks. got some time to buy some other stuff till then.

Hello, Mr. Gerard:

Yes, JMC can fabricate a custom swingarm with the specs you provided. Log in into www.topfueltech.com and check into JMC shop on-line. Enter all specs for your swingarm. Go thru CHECKOUT you will find a section for NOTES, enter into notes section  Dyna rear  Brake Set up, need year of Dyna . There is an additional charge of $125.00 not computed by shop on line which will be added to your sales Total.

If you need further assistance please feel free to contact me.

Maria De Jesus
General Manager

[shovelbill]

hey Randall, here is most of the e-mail i got from Mike answering my query in regards to the backing plates.

Yup gettin pretty pumped. been working on this for 3 years now. Oh sorry forgot to answer that.. the backplates I have holes in them for stands.. and then you just make a set of stands and bolt the filter on .  I just use those nice billet woods chrome short covers and those big 350cfm filters are the same ones as woods.. they come from K&N..  On testing they show a solid 3hp over the shorter one.. even on a 90hp engine.

Mike