The streettrackercafehotrod-Aermacchi/HD "ST"-250

Discussion in 'Some Assembly Required' started by Quickv4, Nov 22, 2009.

  1. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    I thought I would post up here on ADV the adventures with my father and I with building up our ST-250.

    WHat is it?, well, if you take the twostroke SS-250frame, and put the 32HP MX-250 engine in it. It will be of the streettracker, cafe racer, and just hotrod bike. My father made this kind of mutant many years ago, and he finally wanted to recreate it, but make it better!

    I posted on another forum my progress, but since joining on ADV, I thought you guys would want ti see it too!
    #1
  2. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    HERE IS THE OLD POSTS FROM ABOUT 2 YEARS AGO!



    Me and my Dad are going to do our duty at the 105th aniversary in Milwaukee with bucking and rebelling the bigot-ridden "biker dude" crowd there this summer by starting a new cycling adventure....


    MISSION-----Spaghetti Western [​IMG]


    My Dad's favorite motorcycles are by far the Aermacchi/Harley Davidson 2 stroke singles. He has been collecting/tinkering/and riding them since he was my age, and throughout the years, he has accumulated enough parts to put together 4-5 Aermacchis.

    Us kids are getting older, and he is now finding time to actually start woking on them again.

    Our idea is to get 2 running cycles to take to the 105th. in our effort of rebelling the bikers. [​IMG] It is the goal of the Members of the Yahoo Aeramacchi forum to bring atleast 100 Italian Harleys to the rally.

    Our '76 SS250 is running and ridable right now, but it needs a friend SOOOOO....

    We are taking a MX-250 engine and slapping it in a SS-250 frame to make a badass STREET TRACKER. My Dad did this along time ago, making this SS-MX hybrid. It was really fast, putting a tuned 32HP 2stroke single in a 250lbs (wet) frame, it sure goes. My great Uncle Wayne said when my dad made it "hit the pipe", the frame would twist almost 4 inches to one side. Thats how much power it had.

    We will be using the orginal racing expansion chamber (VIRTUALLY NO BAFFLES ----MUAHAHAHA!!!!) that he used over 20 years ago, K&N, and a 32mm rejetted carbie.


    I will be posting pictures and updates as we cram the bike together into the next 8 weeks!!! [​IMG] [​IMG]

    WERE PUMPED


    [​IMG]Heres is what the basic consept will be

    A street-legal version of this ACTUAL flatracker MX-250...

    [​IMG]

    First concept drawings... Yes I know thats an SS engine in there, NOT an MX


    [​IMG][​IMG]

    On the to-do list today...

    -Im going to the local mom and pop auto parts store to get some orange PPG enamel mixed up for the frame.

    -start doing bodywork on a tank and fenders

    -make form buck for fiberglass flattracker seat

    Im also getting the frame back today from the wleders, the upper shock mounts were cut off by my Dad 20 years ago, he had an idea that he could make some lighter mounts, but it was too much of a hassle (move mounts-move wheel-move chain-move sprokets-move engine-modify frame) that we just found the orginal mounts he had cut off and took them to get MIG welded back on.
    The wleder that we took the frames to works on motorcycles also,(has a Venture,Triumph) and he said he had just rewelded some shock mounts on his Triumph!
    I was going to weld them on myself, but I just dont trust my little 100amp stick welder fro that kind of structural thing.

    Speaking of the frame flex again, I wonder how bad it will be when we do our next project, putting a 50HP+ Cagiva WMX 500 single lunger 2-smoke engine in another SS frame, we'll need to gusset it up then!!!
    #2
  3. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    OLD Pics!!!

    Tank bodywork (using SX tank)

    [​IMG]

    The new welded-up shock mounts and patially sandblasted frame (OOOH AHHH)


    My Garage, showing our SS-250 (running, took it for a beat run today around the block for inspiration!!) and the frame.

    [​IMG]

    After a long days work, I now have the frame and swingarm painted.
    I will now take care of the tank's bodywork, and then proceed to lay a base coat on it while the frame is curing for a few days.
    Will also paint small things like kickstand, chainguard, pegs. etc...

    [​IMG]

    [​IMG]
    Heres the latest!!

    Got the tire mounted and balanced onto the rear rim. rear Shocks are installed. Front forks and triple tree installed.

    Tank ready for primer.

    [​IMG]

    We have now A ROLLING CHASSIS!!

    [​IMG]

    Heres todays effort with building the buck for the tailsection. Very time consuming, but is starting to take shape.

    NOTE: we are currently going to use a early 70's Sportster seat as the tail instead

    [​IMG]
    [​IMG]
    #3
  4. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Heres how it looks like TODAY. For kicks a few weeks ago, I tore apart a spare SS wiring harness we had and eliminated the useless bits (for the turnsignals and idiot lights) then retaped and got it on the bike. This was one of the last things that needed to be done in order for it to fire and run.

    The next thing after that to get it to run was to put on a brand new clutch cable and get that adjusted. About a half hours work, and it was done.

    On our nice Jemco flattrack chamber, a hole was punched out where the old rear mount broke off of the stinger, so I made a patch and asked my good friend Kenny to weld it on. He did a great job, and it took little smoothing to get it purdy.

    You can see my homemade bracket for the expansion chamber, and the patch welded over the hole.

    [​IMG]

    tidied up wiring harness...

    [​IMG]

    Only about 5 wires and cables total up near the triple tree; I love simplicity!

    [​IMG]

    The next project is the making of a aluminum battery tray which will hold the tiny AGM (a tiny one is all that this bike needs), and the "top" will have the R/R, CDI box (shown dangling), and main fuse. We may make a provision for holding a tool bag and/or oil bottle.

    [​IMG]

    [​IMG]


    A nice LED taillight will be mounted in the back
    [​IMG]

    The beautiful MX engine, with the 32MM Delorto mounted on it. We're still searching for a 36MM, so if anyone has one, let us know!!

    [​IMG]


    [​IMG]
    #4
  5. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Working on the funky aluminum battery tray right now, will be posting pics soon. But, I cannot find our pop rivet tool, ballz!
    #5
  6. Pigford

    Pigford British

    Joined:
    Sep 27, 2009
    Oddometer:
    995
    Location:
    North Dorset, UK
    Great little project, keep up the good work.... :wink:

    Not so sure on your "CAD" drawing of the proposed finished item though :rofl
    #6
  7. tripletom

    tripletom Been here awhile

    Joined:
    Jul 14, 2008
    Oddometer:
    119
    Location:
    The Lower
    Loving this, orange frame for the MFingWin!
    #7
  8. Maxacceleration

    Maxacceleration Awol

    Joined:
    Oct 9, 2009
    Oddometer:
    2,272
    Location:
    Wa
    Cool two stroke AMF.

    Maker her proud!
    #8
  9. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Ran to Sears and bought a new rivet tool. For 10 smackers, it aint bad at all!

    Now time to fab the battery tray/electrics mount.

    Yes, if had a tig welder (or a Mig with AL wire) this would all be welded instead. I just made sure these rivets were done right, as they can be very strong of the right prep is done of the holes.

    [​IMG]

    basic cradle formed and riveted

    [​IMG]

    cradle inside of frame with battery mocked in

    [​IMG]

    I then created the bottom support and mounting flap which will mount to the inner fender, and keep the tray in place

    The finished support and tab mount fastened to the cradle

    [​IMG]

    assembly in frame

    [​IMG]

    Here's a comparison with the STOCK battery tray, and my custom one...

    [​IMG]

    tommrow will be finshing it offm, and actually attaching it to the bike!
    #9
  10. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    UPDATE 1-3-10


    I went outside when it was 6F and did a few things in the winter sunlight. I put on the flat black tank I had painted (We had a spare SX one that I fixed up and painted, that nice SS tank was NOT harmed in any way) and then I took a quick shot of the bike as it currently.

    I finally bolted up the dash plate to the triple tree, and observed what I still had to hook up in the front end. A speedo needs to be sourced, and the lights still hooked up.

    I also need to somehow fettle a working Veglia speedometer drive out of our baggie of parts we have. I think I can with what we have.

    Once I get the working speedo drive on, I can then button up the front end and get the front brake assembly hooked up to prep the bike for its maiden ''around the block" trip.

    If I can get some things lined up, me and my my father might be riding around on it this spring!

    [​IMG]
    #10
  11. Mista Vern

    Mista Vern Knows all - tells some.

    Joined:
    Dec 1, 2005
    Oddometer:
    16,967
    Location:
    McMinnville, Oregon
    Cool stuff and thanks for sharing the amazing transformation! :clap
    #11
  12. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Dont go away!!! Oh, its not even close to done! Its not even rideable yet! :evil
    #12
  13. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    I found the baggie of Veglia Speedo drive parts tonight and went to town...

    [​IMG]

    I picked the best parts out of the pile...

    [​IMG]

    I then cleaned up the rust on the pinion gear (can be seen in the pic) degreased everything off the case and ferrule.

    I polished the drive case and ferrule to get a nice clean shine.

    I pre-primed the pinion gear bearings with lube and reinserted the assembly into the drive case.

    Although it used to be a perfect press fit, 35 years of flexing, vibration, etc will make the ferrule loose fall out.

    My father and I found out when this happens, the pinion gear will come out with it. There is now a lone pinion gear somewhere along Highway 175!


    To securely fasten the ferrule into the case, you must re-establish the punch marks in the case. I few good taps and wulaa, this ferrule is NOT coming off anymore!

    [​IMG]

    I packed grease into the speedo drive case and slapped the ring gear into the drive! Thats it! lets put it on the ST!

    [​IMG]

    The new refirbed drive on the bike. NOICE!!!:evil:evil:evil

    [​IMG]
    #13
  14. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Playing with timed capture...



    [​IMG]

    [​IMG]


    [​IMG]
    #14
  15. markk53

    markk53 jack of all trades...

    Joined:
    Dec 20, 2007
    Oddometer:
    9,327
    Location:
    Delaware Ohio
    A friend from Australia came over here last winter and bought a Champion framed Harley flat tracker. It was gorgeous, looking a bit like that one, but with black chamber. It actually had the HD serial number Champion used to indicate what it was made for. He had done some research and found the dual sport engines actually worked better on the track than did the MX engines possibly due to different port timing able to be done due to being able to remove material being easier than adding. The MX cylinder may have been just too radical, I don't know for sure. It might even have been flywheel weight of the crank, not sure. The MX may be fine in a street/tracker though... and a lot of fun.

    I like your plan though. I'd like to do a similar thing with a Bultaco Sherpa S type layout as opposed to the Astro... different look... after the SR500 60s style street/tracker posted in the street/tracker threadd.
    #15
  16. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Very interesting Mark. Yeah, it very well could be, the "normal" SS/SX 250 head's ports are less radical, and I can see what you mean by them being more "moldable" so to speak, where one could use the meat of the stock ports to form them to what they desire in them.

    My father made a crazy MX/SS hybrid like this 20+ years ago, and he said it is wicked fun on the street! Bumping the power from 18HP to 32 can make a difference!

    He did try to "top out" the Hybrid (or is it a mutant??) when he had it together. He had it going up to 110MPH:eek1 and the flat-track pipe just kept the engine screaming an' pullin at 10000+ RPM!!! He kept going at WOT and then SCREEEECH, the engine siezed, his rear tire locked up at speed.

    Thankfully he quickly pulled in the clutch quick enough that he did not crash, and coasted to a stop. Waited a few minutes to cool, and it started up, but that engine with that piston and cylinder never ran the same ever again.


    Today we have a NOS cylinder and piston inside...



    Yeah, A Sherpa S would look sweet streetracked! Post it up if you do start on it! I have no experience with any of the spanish makes, but Im guessing there as oddball here in the US as these small italian brands!
    #16
  17. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    More fun drilling holes...

    First the heavy steel kickstand

    [​IMG]

    [​IMG]

    A bit lighter, but still heavy. Maybe in the future we can fab one out of aluminum when we have a TIG someday.

    Then the front fender brace-

    [​IMG]

    [​IMG]
    #17
  18. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Then my father and I toyed with the position of the bobbed front fender...


    more centered ( just a smidge (1cm) biased rearward)

    [​IMG]

    majorly biased towards rear

    [​IMG]

    The less biased one looks better to both our eyes...

    [​IMG]



    The same two positions above, but without bodywork...

    [​IMG]

    [​IMG]


    Trying to figure out how to make a new bead on the front lip????? Maybe someone at a hotrod shop has an english wheel or beader that could reproduce the OEM bead????? OEM one is about 5mm wide...

    [​IMG]
    #18
  19. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    Put the headlight back in and got it hooked up...

    [​IMG]


    Pics for today...


    [​IMG]

    [​IMG]
    #19
  20. Quickv4

    Quickv4 Pro Turd Polisher

    Joined:
    Jul 5, 2009
    Oddometer:
    550
    Location:
    Dickinson, Nort' Dakohtah- Orig. from Wiscowsin
    My father called up charleston cycle in illinois (one of two major aermacchi/hd parts houses in the USA, other one is Moto Italia in Cali) We prefer doing buisness with Leslie at Moto Italia, but Charleston had what we needed.

    We needed 2 new tach cables (both the one we were going to use on the ST, and the one on our stock SS, are both shot!) 18bucks/piece

    Also one Speedo Cable for the ST. Only 18 there too.

    AN one new rubber lower mount for the tank, since the ST does not have one yet...



    Also went to the Decal place and am having repros made of the AMA Harley Davidson Script logo as seen on the Flattraker in the first post of the thread. We have TWO of the originals, and told them to be careful, since they are in the original protective sheath and backing, complete with vintage 3M logo!:evil

    That'll cost us 50 bucks, mostly for the drawing fee ($25) to transfer them to the computer. Then its 12 dollars/decal after that.
    #20