I got my 'combat scrambler' back on the road!

Discussion in 'Airheads' started by supershaft, Oct 17, 2012.

  1. supershaft

    supershaft because I can

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    It's been 13+ months since my shock stud snapped. I got a lot of kind words of support and some cold hard cash to boot although I still wish Norton Lory never did that donation thing. Nevertheless! The money has helped! Thank you again everybody!

    It's been too long since I rode it last. My butt dyno is a bit out of practice but with 200 miles on my rebuild the thing is definately not running worse! It goes through the first three gears and 105mph pretty quick! 99 and 99.5 leak down at 200 miles (that is not going to happen if you don't stagger your ring gaps OR break it in like you are 'suppose' to). The valves are not leaking one bit thank you very much robtg! The rest of his machine work was top notch too! I revved it to over 8k at about 150 miles on the new top end. I started with 145 mains just to be safe and I am already back down to 135's! I was hoping for ten more hp and I think I am close. Not bad since I already got a lot of the easy gains with my carbs and cam.

    Thanks again everybody! I am going for a ride right now. I am still figuring out wear to run my valve lash with my super beefy 4130 pushrods.
    #1
  2. RecycledRS

    RecycledRS Along for the ride

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    Good to hear your back two wheelin. :D Try and keep those wheels under you:1drink
    #2
  3. Beater

    Beater The Bavarian Butcher

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    Pic's or it didn't happen :evil

    PS - Glad you're back in the saddle :freaky
    #3
  4. supershaft

    supershaft because I can

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    Sorry beater. Still no pics.

    I am going to have to run my cold valve lash a little bit in the negative in order to keep my lash where I want it when it's hot. I am thinking it will still start just fine.

    I don't think my valves are floating with those heavy pushrods but I am not positive about it just yet. IMO, that is easier to monitor in third and forth (I have still never run it up in fifth but I don't want a 135mph speeding ticket. Third and fourth are a little to well over the ton as it is. Plus I have a slightly bent front wheel. I am sending off a spare to be straightened today or tomorrow. It is still a work in progress at this stage but all is looking good.
    #4
  5. Bigger Al

    Bigger Al Still a stupid tire guy

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    Good to hear the bike is back on the road!

    The next project should be a simple digital camera and tutorial on how to post up your pics. :deal
    #5
  6. hardwaregrrl

    hardwaregrrl ignore list

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    Way to go Billy!!!! Glad you're back where you belong!
    #6
  7. Airhead Wrangler

    Airhead Wrangler Long timer

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    Welcome back! Just curious, what was the fix for that snapped stud? New final drive or did you weld a mount onto the swingarm? I've never been a fan of the design for the lower shock mounts on the mono road bikes or 1st gen paralevers. I'm guessing you probably aren't a fan now either.
    #7
  8. supershaft

    supershaft because I can

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    For right now I just have the stock setup back in there. I drilled and extracted the stud no problem. I got the new stud in a matter of days through SF BMW. No damage to the FD at all excepting a broken off fin and some muff marks that I smoothed out with a die grinder. Most of them you don't even notice with the shock and muffler back on.

    The only improvement I can figure to make is to make the inside part of the stud 15mm versus 10mm. That inside junction from 15mm back down to 10mm is right where it broke.

    I can't see any advantages between any of the stud setups that I have looked at other than sharing the load with two shocks versus one?

    Now that I am thinking about it I think I am going to double check and make sure the 15mm ID portion of the FD didn't get wallered out at all. That stud needs the support through there! I have a number of spare FD's so I am no worse for wear either way.
    #8
  9. supershaft

    supershaft because I can

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    When I get my straightened front wheel on I am going to make some airbox setup experiments. Now that it's running much stronger everywhere for the higher CR, bigger intake valves, dual plugging, remapped advance curve, port work, and maybe even my monster 4130 pushrods, I think I can afford to gain a bit on top for a loss down lower. It's all a bit of a guess right now since I am trying to monitor too many things at once but it seems like I am running out of air at top rpm more so than before the mods. My hunch makes sense since it is making more torque everywhere and peak air intake goes hand in hand with and in direct proportion to peak torque. I finally might have outgrown my almost stock box? It won't take too long to find out since I have many modified setups waiting to re-test. I am going to try shorter velocity stacks too. We'll see. I certainly won't give up too much for peak hp. Peak hp? First you have to GET to peak hp! :freaky
    #9
  10. RecycledRS

    RecycledRS Along for the ride

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    Take some pictures:lol3
    #10
  11. craydds

    craydds Long timer

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    Supershaft, find a local inmate who can make some pictures and post them for us. We want to see your bike!
    #11
  12. ontic

    ontic

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    Congrats on getting back on the road SS but it's about time you learned to post photos:deal. Cheap digi camera, even just a camera phone, this stuff is so old now you can pick up something decent for next to nothing (or indeed for nothing). Any number of us can run you step by step how to upload your images to a hosting site and then post them here.
    Stay safe
    #12
  13. Uncle Pollo

    Uncle Pollo Long timer

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    Ss find a 12 year old kid with a smartphpne and give him 5 bucls to ppst pics pf your rig.
    #13
  14. supershaft

    supershaft because I can

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    Thanks guys. I have a camera. I bought it a few years back. First one I have ever owned. Now I need to start taking pictures for starters. I took some pictures of a MV 150 that I fixed. They are still in my camera. I have felt the erge once or twice now but don't hold your breath.
    #14
  15. supershaft

    supershaft because I can

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    Well, a local inmate is going to show me how to do pics some time soon.

    I just cracked the throttle open in first at about 3000rpm. At around 5k the front end came up and stayed up until I let off for second. No bumps or anything. Just a pure 100% power wheelie. Remember that with my CR tranny my first is almost as tall as a normal tranny's second gear. Out on the hiway at 90mph with fast traffic and you want to get around some cars? Crack open the throttle and you are going 120 lickity split. I LOVE it!

    It idles different with the higher compression ratio. There's a lot more boom in every pop.

    Some admirers of my bike in SF called it a 'cafe racer'. Cafe racer? Cabriolet poser? No. I had to tell them that my bike is a TT racer. That can stand for Tourist Trophy racer or Tavern to Tavern racer. Take your pick!
    #15
  16. Bluethumb

    Bluethumb Been here awhile

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    I'd like to know the specifics on this build. Power wheelies at will? 135 mph? From a street airhead motor? I owned a Ducati Multistrada which put out an honest 85 hp at the wheel and I could only see an honest GPS verified 135 mph in perfect conditions, as in a long slight downhill with no head wind and it took everything for that motor to go a real 135. I'd bump up against 140 but very rarely. And I weigh 155 lbs. I owned a 916 that would lift the front wheel when I powered shifted into second. But an airhead is far from a Ducati 916.

    I've owned some powerful airheads and might see an honest 120-125. The difference in pushing a bike from 120 to 135 is huge requiring exponentially more h.p.

    Find someone you'll loan you a GoPro. Post some pictures.

    But Supershaft, I'm calling bullshit until there's proof.
    #16
  17. bgoodsoil

    bgoodsoil Dare to be Stupid

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    I don't have a problem believing the power wheelies. I had low compression r100 pistons in my bike for a while and could do power wheelies in first gear. Man, they're hard to control! That was with low G/S gearing and the fact that my boxes hang behind my axle with that short monolever swingarm though.

    Glad you're on your wheels, SS. Seems like you've got a fine 'build thread' right here to lay out your set-up so the rest of us don't have to spend 30 years figuring out how to do it. I give it 3 weeks before it gets sent to the basement
    #17
  18. supershaft

    supershaft because I can

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    I have had the same experience bgsoil with r80's with 1000cc cylinders on them! The main difference with my story is that I am running a 33/11 FD with a close ratio tranny. Big diff in first gear gearing!

    BT, I had two friends back home with the same hotrod tricks done to their early '90's SS's. They were pulling around 88hp on their dyno. They hauled ass. They would power wheelie through first gear EVERY time you were hard into it and they have real tall first gears too. They would power wheelie through second half the time. I have ridden the new retro Ducati's that are suppose to have 85hp stock. I don't think they do and I know their midrange suffers big time for what little more they got on top over the older 900's. We'll see but I think my airhead will now out pull one.

    My bike power wheelieing at will? It has done it ONCE! But I am tickled pink at that with my gearing. 135mph? I have never revved it up in top gear but if it will pull 8k rpm in top gear and I think it will and if pj's top speed/gearing chart is right, I think it will. It would easily rev to 8k rpm in fourth BEFORE I did a bunch more mods to it. According to my speedo that I know reads a little high and pj's chart, that's a 120 something mph right there. It will pull 8k in fourth now NO problem! Like I have said before, according to pj's chart, speed gun displays, and tickets I get, I don't think my speedo is that far off. I use to do machine and fab work on and help with a race airhead that would pull right around 155mph at Daytona lap after lap. Those are the ports I conservatively mimick when I did some port work on my bike this last rebuild. I think it helps!

    Proof? That cracks me up bt. What can a photo prove? Just about nothing in my book. Same with dyno charts. We could race! I do think I am going to out run your Multistrada IF it is stock.
    #18
  19. chasbmw

    chasbmw Long timer

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    Taking mph figures from a BMW speedo is a bit like relyin on (politician of your choice) to tell the truth
    #19
  20. supershaft

    supershaft because I can

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    That's why I have backed mine up with radar guns and gearing charts. That and accounting for some error. I realize my tach can be off too. Plus the fact that it tops out at 8k. It's the radar gun displays and tickets that tell me mine isn't that far off. That and, if you subtract a few MPH, it all lines up with pj's gearing chart.

    I remembered last night that I passed a line of cars up a long hill with a at least piped and chipped Multistrada a year or so ago. (these guys spend MONEY on there bikes). We were side by side and we were both in a hurry catching up with one friend on a 1198 and the other on a gixxer 1000. He out pulled me a bit but my bike is running a lot stronger now. My friend on the 1198 also has a piped and chipped Multistrada. Hopefullly we will get the chance to do a quick from first gear roll on race up to 120 or so and see where we stand.

    My main point is that airheads do not have to be tractor motors and boat anchors. They are really pretty easy to get running pretty strong very reliably. It's just that a lot of people go about it ass backwards IMO.
    #20