what did you do to your motorized bicycle today?

Discussion in 'Motorized Bicycle General Discussion' started by Skarrd, Oct 25, 2010.

  1. young grease monkey

    young grease monkey New Member

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    Re: what did you do to your motor bike today?

    the reason it doesn't leak is that the head is thin enough it will bend when you torque it down. it is bad for the head. can someone else back me up? just because it works, doesn't mean it's a good way to do it.and if you get loeaks because one isn't torqued the same, that diffinetly means they are not flat. you will get no leaks if one bolt is torqued to only 5 ft/lb, but it will loosen quickly, if you have a good flat surface.
     
  2. DaveC

    DaveC Member

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    Re: what did you do to your motor bike today?

    Well, using a sanding pad is a bad idea because what you end up with is two convex surfaces that your trying to seal. A pad sander has a tendency to round off the edges because theres nothing to support the pad so the edge of the pad will exert more pressure along the edge over removing material from the center because there's more pad to resist deforming. This tendency gets more pronounced the further from the boltholes you get. It will seal ok at first but the problem is insuffecent contact area for both heat transfer and to prevent walk. Walk is when the head squirms around under heat and can actually move quite a bit, mechanically speaking. Eventually you will get a loss of compression from leaking but.. if you re-torque every two tanks or so and do it cold you should be ok...

    And just about any piece of glass will work. It doesn't have to be 1/2" bullet proof glass. I use a mirror. NAPA has packs of wet/dry sandpaper from like 220-400 and 600-1000 grit I think it is. That and some oil and follow a guide and you will be successful. You don't have to grind hard, the oiled wet/dry cuts very well. Just because you don't see huge results it's still working. I actually stop at 400 grit because I use Permatex Spray Copper Form-A-Gasket to help seal. I've used it in my race motors for years and have never had a gasket leak.

    I also have lapped computer processors and heatsinks. You do need to do those up to 2000 grit so they take much longer to do than a head and jug in a HT motor :)
     
  3. DaveC

    DaveC Member

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    Re: what did you do to your motor bike today?

    This has stuck in my head for days. How the **** did you strech a steel frame 1 1/2" with a screw jack? It scares me half to death, there must be weakened or broken places in the tubing.


    ...or did you mean "spread" the frame?
     
    #2943 DaveC, Jan 14, 2012
    Last edited: Jan 14, 2012
  4. breno

    breno New Member

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    Re: what did you do to your motor bike today?

    Found that the exhaust wrap had def. made it run leaner but I have also lapped the head down and changed the plug to a BP6HS. The pic is after a wot run so Ill be going back to a 75Main jet in the 18mm mikuni and have a fiddle with the needle setting if needed.
    Might even play with the pilot jet for the low end again just got a 15 pilot jet interested to see how it goes coming from the 20 as I can still see a little blue smoke just off idle and its not that smooth at 1/4 throttle when going slow. Failing that I'll be taking a file to the slide as I found out apparently I cannot buy different size needles and slides from the fella here in Australia due to them just being a "cheap" carb that is used for mini bikes and what not that ppl dont really go to that length of effort playing with them...in short theres no market for him to keep them in stock..pita

    Anyways tried to do a compression test last night and it was pretty much impossible with the crappy tester I had. Couldnt get a good enoough seal even with thread tape and tightening the **** out of it (I was using soapy water which was sprayed on to check for leaks). Ended up getting a highest reading of 140psi and I am still not confident that it wasnt leaking as I could see bubbles still. The 1st few times I tried I was only getting 75psi but I had a sneaking suspicion it was telling me porkies hence the soapy water method. Anyway anything over 140psi is good enough for me :)
    The new style magneto should turn up tomorrow thank goodness.

    Cant wait to have this bike 100% dialled in sooo dam close its eating at me.lol
    Wont suprise me at all if it'll tip over 65km/hr with the 44 tooth if it does I'll have someone drive beside me and record it..keeping in mind I'm 6ft 5 and weigh 105kg should be a solid effort but I think its achievable.
     

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  5. CTripps

    CTripps Active Member

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    Re: what did you do to your motor bike today?

    I swapped brake pads front and back for new ones today, made a minor adjustment to the clutch, lubed the gearbox and went for a short ride after tweaking the brakes. It now stops comfortably within the thirty foot length I marked out. Had to watch it in the shady areas, we actually had snow last night in Vancouver so there's a few slick spots and a small patch or two of it left on the pavement.
     
  6. rustycase

    rustycase Gutter Rider

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    Re: what did you do to your motor bike today?

    Yes, I also agree that using an orbital sander to lap a cylinder head is probably NOT the best idea. It will never be flat like when done on a glass plate.

    Which is not to say it will not provide results better than a factory stock ht! lol

    Best
    rc
     
  7. Fugi93

    Fugi93 New Member

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    Re: what did you do to your motor bike today?

    I opened up my new HOOT G5 gearbox for inspection. Found a defective spring on the clutch and removed it and and put it back together with only 3 springs. Takes off like a car now. I can now cruise at 4 mph with no clutch slippage. I am thrilled at how it truned out - all by accident! It took 14 mph to quit slipping before.



    [​IMG][/IMG]
     
  8. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    Re: what did you do to your motor bike today?

    I had mistakenly put too much oil in the tank, so my fuel/air ratio was @ 50:1. Carb adjustments were made to let the engine run better. After 5 days of commuting, I was down almost 60 ounces. I decided to add another 2 quarts of gas. Mixing this amount with 100:1 would raise my incorrect mix better than 83:1 f/a ratio.

    After the fillup, the bike wouldn't idle. Being that I would be riding on the sidewalk to McD's down the hill, I left my tools and backpack @ home. Fortunately, I was able to use my fingernail to adjust the carb adjustments.

    Bike riding fine now, ready for the commute on Monday.xct2
     
  9. andrewflores17

    andrewflores17 New Member

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    Re: what did you do to your motor bike today?

    road my bike to the local park about a 9 mile round trip about half way through realized i should have put something warmer on my head than a ball cap ears nearly froze off brrr
     
    #2949 andrewflores17, Jan 15, 2012
    Last edited: Jan 15, 2012
  10. isldtime

    isldtime New Member

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    Re: what did you do to your motor bike today?

    Rode It..

    Really over the last week I've added a suspension seat post and upgraded the front V-brake to quality parts and the rear from center pull to quality V-brake. Made a big diff.
    Every time I ride it now it runs and rides better and better. Up to about 20 miles on it now and no major problems but the pre-flight is the most important item.drn2
     
  11. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    Re: what did you do to your motor bike today?

    How about a helmet to keep your head protected from the weather and other stuff.

    Please ride safe. One of our members fell off his bike on his maiden voyage.....and died.
     
  12. GearNut

    GearNut Active Member

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    Re: what did you do to your motor bike today?

    I am not understanding how putting too much oil into your tank could possibly result in a fuel/ air ratio of 50:1.
    The engine would not run at such a lean ratio. common ratio is 14.7 to 1.
    14.7 parts air to 1 part fuel.
    Many modern engines are tuned to run at 15:1, some even 16:1 which is ungodly lean for an IC engine. All in the name of a hotter burn and reduced tailpipe emissions.

    Perhaps a 50:1 fuel to oil ratio?
    Switching from a 100:1 fuel to oil ratio to a 50:1 ratio certainly would necessitate re-tuning the carburetor as the 50:1 ratio would be heavier than a 100:1 ratio and flow through the fuel ports in the carburetor at a slower rate.
     
  13. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    Re: what did you do to your motor bike today?

    Oops, my bad, lol. You are correct.laff

    fuel/oil ratio.
     
  14. happycheapskate

    happycheapskate New Member

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    Re: what did you do to your motor bike today?

    I rode my tanaka bike for hours today. I pedaled with a social bike group, ate some tacos for dinner, then motored around through a couple tanks (1/2 gal) of gas to break the engine in and get out of the house a while. The Tanaka33 filter cover fell off. Ugh!
    I suppose I will have to purchase another, or figure out a substitute.

    Edit: I made a whole filter box from a snuff can and foam . Nothing new to the world, but good enough for small engines.

    Scott O has posted links to Daves Motor Sports which has all the relevant replacement parts like velocity stacks, filters, and filter boxes.

    http://motorbicycling.com/f51/tanaka-33-filter-cover-replacement-36440.html
    Thread about our findings.
     
    #2954 happycheapskate, Jan 16, 2012
    Last edited: Jan 18, 2012
  15. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    Re: what did you do to your motor bike today?

    I rode my bike to town today, about 6 miles. The bicycle chain fell off 3 times, which was kinda strange. After lunch, I was heading home when all **** broke loose. :-||

    The chain jammed, then broke the derailleur hanger. This threw the derailleur into the wheel, broke two spokes and the plastic chain guard behind the cassette. Thankfully, the LBS had the right parts. I should have the bike up and running for my commute tomorrow.

    Can't wait for sunrise!xct2
     
  16. GearNut

    GearNut Active Member

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    Re: what did you do to your motor bike today?

    Yikes, 5-7!
    I am glad to hear that you did not crash during the catastrophe!
    That was alot going wrong all at once, sorry to hear about it. :(
     
  17. DaveC

    DaveC Member

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    Re: what did you do to your motor bike today?

    Suprizes me when you have problems. You work on your bike almost all the time, I don't think there's a better maintained bike on this forum. Of course it has to be. You use it for general transportation, something most don't.

    Is it overly complex or is it a case of the bike finding the weak link and breaking it? ;)
     
  18. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    Re: what did you do to your motor bike today?

    The setup is fairly simple. If I could run a #40 chain or better with an internal hub, it'd be more dependable. Dead-on chain alignment, no derailleur, no cassettes, no chain jumping. My next project will have a NuVinci hub, so that might work better. If not, I'll try a Sturmey-Archer hub.

    Also, I think I need to doublecheck alignments on both engine and bicycle chains. That might be the cause of most of my chain problems.

    The absolute weak link is the light-duty 8-speed bicycle chain. With daily use, it takes the abuse for several months, then breaks. That's what I'm presuming. Thank goodness the Tanaka engine is dependable. The engine's last issue was my fault. I richened the oil ratio, because I simply couldn't take the chance of burning the piston. The fuel/oil ratio raised 2 days ago, when I pumped in 2 quarts mixed @ 100:1 to the remaining quart @ 50:1. Engine is spitting a little oil, but should be fine on the next fillup.

    The AVID 203mm brakes are great. The Big Apple tires work well, once I lowered the gearing to compensate for 27" height. No probs with engine or fuel system. The gearbox circlip wears out every 6 months, but that's a 40-cent fix. Gas mileage is excellent @ 125mpg. Power is awesome. Low, midrange and top end is great, as is hillclimbing. Noise is not an issue, even with an expansion pipe. The Diamondback Response bike handles very well.

    I save about $5,000 yearly by running this bike. It replaces the "third car" between three drivers on busy schedules. It saves me untold stress by not having to deal with gridlocked traffic. I get free covered parking next to my co-workers, who pay $100-something monthly. If I drive to work, I get to circle the blocks, then park a quarter-mile away in the hot sun, w/bird doodoo on my car.

    The shifter cable needs replacing, so I'll fix my bike tomorrow. No probs, becuz I need to work late. Instead of riding home after sunset, my wife and I can carpool for a couple weeks.

    No matter how much it costs to fix my bike, car repairs would be 20 times as costly.

    And I REALLY like fixing my bike and figuring out how to make it better.dance1
     
  19. 5-7HEAVEN

    5-7HEAVEN Well-Known Member

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    #2959 5-7HEAVEN, Jan 17, 2012
    Last edited: Jan 17, 2012
  20. anim8r

    anim8r New Member

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    Re: what did you do to your motor bike today?

    It's not a motorbike, but I got an old Toro S200 snow thrower today that I'm pretty excited about. I don't know if it works yet, gotta gas it up tomorrow.
    This'll be my 1st chance to see if the troubleshooting skills I learned for my china girl will apply to a different motor. Two major differences I already noticed: the snow machine has a pull-start & an ignition key. I've never worked with either, so it should be interesting.
    If it doesn't snow soon I'm gonna figure out a way to ride this thing...
     

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