airhead noob

Discussion in 'Airheads' started by scout18, Aug 24, 2012.

  1. disston

    disston ShadeTreeExpert

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    Here is the web page from the manufacturer Dynatech. They are the most common ones to find, there are others.

    http://www.dynaonline.com/skins/products/accessories/Dyna_Boosters/

    Here is a used one being sold on Ebay.

    http://www.ebay.com/itm/BMW-R90-6-R...Parts_Accessories&hash=item2a21f0eabc&vxp=mtr

    The stock wiring is moved to install the booster. Instead of the black wire that goes back to the points from the right coil look for a wire going to the booster.

    Edit: I just noticed that this is the single plug ignition model. I didn't know, they have a dual plug model? I don't see any reason to have this. At this point in the system one or two plugs doesn't mater. Does it?

    Anyway the dual plug model probably looks very much the same.
    #21
  2. wirewrkr

    wirewrkr the thread-killer

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    At Dyna when they say "Dual Ignition" they mean dual Points, not Coils.
    You want the part number DBR-1.
    I personally would not buy a used one unless I knew the seller and the history of the bike it was on etc.
    That's just me though when it comes to electronics. If the magic powers have been released from the little red box, I cannot see it so...................
    #22
  3. disston

    disston ShadeTreeExpert

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    Mr. WW

    A good point. You cautious devil you.
    #23
  4. scout18

    scout18 Been here awhile

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    I DO have a red booster box thansk for the pics to show me what to look for. Its right behind the coils on the underside of the top frame tube. There was a lot of corrosion in the rear coil holes for the bottom plugs. I'm pulling them next.
    #24
  5. disston

    disston ShadeTreeExpert

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    Well it only took two days...Sheesh. :lol3:lol3
    #25
  6. scout18

    scout18 Been here awhile

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    I"ve been elk hunting. Sheesh!:wink:
    #26
  7. scout18

    scout18 Been here awhile

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    So I checked the points gap it was perfect. I pulled the plugs and had spark on the left top and right bottom. The connections on the other two coil ends of the spark plug wire were so corroded they were not getting any spark. I cleaned house up there and and put in new plugs. I found the median range of the carbs with the idle air screws with out shorting the plugs. Next I will balance the airflow at idle with the idle adjuster screws so they are drawing the same. I do need a carb rebuild and I need new throttle cables. She runs and rides but will be better with more love. :D
    #27
  8. hardwaregrrl

    hardwaregrrl ignore list

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    It is a remote possibility you may have a 336 cam....it could possible cause your crap idle problem. It is a remote possibility, given the OP hotrodded it a bit. Any way to find out if the cam has been changed???
    #28
  9. scout18

    scout18 Been here awhile

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    I'll have to ask him. very possible.
    #29
  10. boxerboy81

    boxerboy81 Stay Horizontal

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    Have you cleaned out the idle jet passage?

    I've used fishing line to shove up/down the hole then squirt, then prod again, then squirt again and finally blow thru.
    #30
  11. supershaft

    supershaft because I can

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    Except that there are quite a few on this forum that will tell you that their 336 idles real well. 336 or not, that isn't the reason for a crappy idle.
    #31
  12. Cordless

    Cordless Two Wheel Addict

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    Elk Hunting? You are going to need a g/s.
    #32
  13. scout18

    scout18 Been here awhile

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    Elk hunting was a success and real life took back over. We are green loctiting in the left rear wheel bearing outer race and we shall see what happens Monday night with that
    #33
  14. disston

    disston ShadeTreeExpert

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    Make sure you follow directions when removing and installing wheel bearings. It takes heat. Most modern versions have you use hot water for the heat. They think it is safer than the old method of a heat gun. I use a propane torch. Just be careful to not over do it and keep the flame moving.

    Failure to use some source of heat to expand the Aluminum hub can ruin the wheel because the bearing will spin the outer race.
    #34
  15. scout18

    scout18 Been here awhile

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    I have been researching that in exhausting detail. I used a propane torch to get it hot. I followed the directions here,

    http://w6rec.com/duane/bmw/wheel_bearing/index.htm

    and out hey popped slick as could be. Following the directions again I put the new ones in just as easy as the old ones came out. The reason I took them out in the first place was that in a post purchase inspection it was pointed out that there was a lot of play at the rear wheel. On further inspection it was revealed that the left bearing cup had spun in the hub. After much gnashing of teeth and hair pulling it was decided to use a high temp variety of green loctite to hold it in while I search for a reasonably priced rear wheel to replace this one with. There is also the option of machining out a bit more of the hub to install a sleeve to fit the bearing cup into. Monday night I'll put the wheel back on the bike to set the bearing preload and then move on to the rings to see whats up there. The compression test showed 150 and 160 put with a leak down of over 50% in each cylinder.
    #35
  16. DoktorT

    DoktorT BigBrowedNeandereer

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    Surely there is a problem with your procedure or instruments. You simply cannot have 150lbs compression with 50% leak down. Violation of the law of physics here.
    #36
  17. scout18

    scout18 Been here awhile

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    I didn't do the test but isn't the point of a leak down test to see if a piston seals well enough to show that kind of compression but be unable to hold it? I'm not sure why it's a violation of the laws of physics. I'm just a 'lectrician:D.
    #37
  18. DoktorT

    DoktorT BigBrowedNeandereer

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    High spec comp should be 145 to 150. At that level, leak down will be around 2 or 3%

    Leakdown at 110lbs comp will be some 80%-90%. Any less than 90% is rebuild time.

    You simply will not see 50% leakdown at 140lbs. Could be you had a good test for comp then a bit of a piece of crud ended up fouling a valve. Run the motor to full temp then test again. Ane the whole idea behind a leak down test is to determine where the loss is occuring, valves int or exh or rings or head gasket or a combination.

    I doubt you would have any potential to start the motor at 50% leak down, and then if it did would run like crap and certainly would not idle.

    You got some bad data due to procedure or instruments.
    #38
  19. scout18

    scout18 Been here awhile

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    Ok I'll do that. I am getting a lot of white smoke after it's warmed up.coming out the right side but I'm pretty sure that is because the crankcase breather hose is vented to that side. again it's supposed to have high compression pistons in rings from a 900 in it. It runs great on the highway and pulls like everything from 60 - 90. Around town as it warms up stop light to stoplight is when I see the smoke..
    #39
  20. DoktorT

    DoktorT BigBrowedNeandereer

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    Burning oil can come from the oil control rings or valve guides worn. That would be dark smoke. If light smoke, running too rich. You have a basic issue that correct diagnostics can find.
    #40