It Lives! Kustom Kruiser Roadster, My First Build!

Discussion in 'General Questions' started by midlifecrisis, Jul 21, 2008.

  1. midlifecrisis

    midlifecrisis New Member

    Fired her up yesterday afternoon and took her for a short spin. I still need to do quite a bit of work, so consider this a sneak preview of the finished machine. The bike is a Kustom Kruiser Roadster ($300 at local bike shop), and the engine is a HT I bought from "powerking" off ebay. Some thoughts, issues, etc.:

    I mounted the engine on the seat post, and fabricated a crude front mount from simpson strong ties from home depot. My thinking was that given my limited fabrication abilities, the motor would be more secure if I used at least one of the original engine tube mounts. I opted for the back one because 1) I thought it looked better sitting farther back, 2) I thought it would be less likely to interfere with the pedal system, and 3) I thought that minimizing chain length would reduce the chance of problems arising from of chain slap. I am pretty happy with how it came out.

    The bike has a coaster brake, so I had to ream out the center hole of the sprocket and recess the bolts (using new hex key bolts). It would seem that someone would make a sprocket already set up for a coaster brake, but I never found one. Reaming out the hole was a bit of a pain, as the sprocket metal is very hard. I used a 1 1/2" drill-mounted grinding wheel (ace hardware), and chucked it up in my drill press. I used some scrap metal to bevel the leading edge of the grind stone so it would fit into the existing sprocket hole, and forced it to grind away with the drill press. the stone was consumed in the process. I also had to grind down the dust cap to get it all to fit. It then bolted up fine, but getting the sprocket perfectly aligned and true must be an art form. I got it pretty good, but there is a bit of vibration under power that I'm sure is related to the sprocket. I'll probably go with one of those whole-hub aluminum clamshell hub adapters I've seen on ebay, but want to fully consider my options. Ideally, I would like a complete hub with a bracket for the sprocket, as well as a place to hang a brake disc. Anyone have any suggestions? Best place to buy the hub adapter?

    The bike comes without a front brake, so I mounted a side-pull caliper I bought from spookytooth. As mounted on the springer fork, the pads didn't reach the rim, so I made little aluminum arm extenders, probably not a great idea. The brake does work, but it is relatively weak. I am going to be putting a S-A dyno/drum brake hub on the front, and lace the wheel with stronger spokes. Bikeman has the hub for $65. Does anyone have suggestions on length/gage/source for spokes, or any guide on re-lacing the wheel?

    Chain clearance issues. Pedal chain has to be routed around the engine (not done yet). Tried a ghost sproket, but couldn't get it up high enough to go over the engine, so I decided to route it under. I'm going to use a chain tensioner wheel, bend the bracket 90 degrees, and bolt it to front engine mount. Still waiting on the part. The engine drive chain needed a wheel to clear the lower part of the frame.

    Remaining to-do list:
    - get pedal chain on and routed under the engine.
    - custom gas tank (I'm kicking around some ideas, and will build soon)
    - reinforce/rehang/modify fenders, chain guards, etc.
    - better rear hub
    - front brake
    - black leather pannier bags (any suggestions?)
    - apply for California plates
    - rear rack (with side surfboard carrier)
    - retro-look lighting
    - etc., etc., etc. (I doubt I'll ever really be done)

    Attached Files:

    Last edited: Jul 21, 2008

  2. hellbilly

    hellbilly Guest

    That is COOL! I can see you have made alot of progress. You will really like the front hub brake. The ones I got came from Bikeman also. You could take your front wheel to a bike shop and they can figure out what spoke length you need and relace the whole thing. They will have a trueing stand. My shop charged $65 for the parts and labor, I thought $$ well spent. I don't think you will need a heavier spoke on the front, maybe just a criss cross pattern. As for the back wheel, If you are going to use the setup from the kit you may want 12g spokes. If you use the clam-shell adapter (Livefastmotors), your spokes will be okay as the hub adapter attaches directly to the hub. It takes alot of the torque and tension away from the spokes. It is also alot easier to center. You are on the right track with a tensioner on the pedal side too. I am wondering if you will be able to notch out the chainguard and fender? To me, they just look better with the bodywork and serve a purpose. The blacked out engine looks great! I have seen guys use a Dremel to grind the paint from the outside edges of the cooling fins for a little contrast/custom look. When you get some time you will want to do away with the filter on your fuel shut-off and install an in-line filter. I am happy to see that with your engine in that position you were able to clear the frame with the motor chain. Now I won't have to try 10 different ways. Please keep us posted with your progress and any problems that arise. I am interested if that front mount works out well without too much vibration, and I will do something similar on mine. You will find alot of great ideas on here, it looks like you are well on your way. Here is a Dyno Kustom Kruiser that made Bike Rod N Custom magazine. Check out the bent springer fork. It sits way low!! Bet he has to make sure the left pedal is in the up position for a left turn and same for the right! Good job so far!
    Last edited by a moderator: Jul 21, 2008
  3. azbill

    azbill Active Member

    nice roadster dude !!! :D
    good choice on the front hub, I have a sturmey XF-D drum hub and love it
  4. midlifecrisis

    midlifecrisis New Member

    That Bike is Unreal!

    I can't believe that bike is rideable! I agree with you about the fenders and chain guard - they really add something to the bike. I'm going to reinforce the mounting holes (jb weld washers inside), and make new (stronger) support struts. The stock ones are pretty flimsy. I don't think trimming the fender and chain guard will be an issue, as I have a bosch jigsaw that cuts metal fairly well. I may add a layer of fiberglass inside the fenders to stiffen them up a bit.

    I'm going to add a fuel filter, I was just anxious to fire it up! I think the motor mount will be fine, but the hub adapter is going to be a definite purchase. Another thing I was thinking about was a custom exhaust. I was thinking of maybe cutting the stock exhaust in the middle, making a center length of pipe out of copper tubing bent to fit, slitting the ends of the copper tubing, and then crimping it all together with hose clamps.
  5. hellbilly

    hellbilly Guest

    Those sound like great ideas! You're gonna have a sweet ride there. Tell me how the bike rides under power. It is a pretty lightweight bike so it should scoot right along. They seem real comfy too, but a bit hard to pedal on the inclines.
  6. graucho

    graucho Active Member

    Great job. Great look. How much chain do you have to add for the stretch models?
  7. midlifecrisis

    midlifecrisis New Member

    Azbill - thanks. I look forward to getting effective braking, as its really not particularly safe at the moment.

    Graucho - I had to add about six inches of chain to the standard length to make the distance, even though I mounted the engine all the way back on the seat post. I also had to make my own clutch cable, and buy a longer throttle cable, as the ones that came with the kit were too short.

    Hellbilly - right now it vibrates a lot under power, which I'm sure is due to the rear sprocket. I'm guessing it'll do 25-30mph (no speedo yet). I'm hoping that it'll top out under 30 (CA law) so I don't have to detune it to be legal, and I may drop the gearing a bit, as I live at the base of a large hill (Mt. Soledad), and want to be able to ride it over the top. I agree with you about pedaling the bike - I would have never bought it to ride as a bicycle, but the motor cancels out any issue with pedaling.
  8. D's Bikes

    D's Bikes New Member

    Very cool I just picked up the identical Dyno Roadster a few nights ago with plans to put an engine on it very glad you have done one it really gives me alot of thought into things I have to mod and make extra time for. This is my 4th build so it will be fun to finally fabricate a bit.

    Have you ridden it yet? I love riding mine without the engine can't wait until I have it all ready...the suspense is killing me
  9. midlifecrisis

    midlifecrisis New Member

    Quick Update

    I bought the sturmey-archer fdd drum brake/dyno, and it is exactly what the bike needs. I consider this a must-have uprade.

    I also bought the livefastmotors clamshell adapter, and am a bit disappointed. The adapter will not fit without modification (coaster brake hub diameter slightly too big.) Also, it comes with a slotted brake arm extender, whereas the shimano hub on the bike has a star shaped interface. Livefastmotors doesn't say anything about the different type of adapters, and they were not interested in allowing me to return the clamshell adapter. I have made it work, but have now had some of the bolts pull out and am in the process of drilling out the sprocket mount holes oversize and tapping them to allow bigger bolts. In hindsight, I would look at getting something like the grubee hub (are these still available?), and may end up going that way regardless.
  10. softride

    softride Member


    Cool to see one of these being done
    it look to be the same model as I am going to use for my JET project
  11. Mountainman

    Mountainman Active Member

    yaaa - that's a nice looking MB

    I think that you may wish to move the Calif plate up on the list

    the poolice love to stare at mine -- just a little

    then they drive off

    allways a good thing -- Mountainman
  12. midlifecrisis

    midlifecrisis New Member

    yes, got the plate, so now I'm pretty much legal. I'm working on a custom gas tank (not much time lately), and will post more pics when I'm done. I do have the pedal chain routed under the engine now. I used the chain tensioner wheel that came with the kit, bent the bracket 90 degrees, and bolted it to the front engine mount. Works like a champ. I glassed the inside of the fenders and chain guard, and mounted them back on. The rear fender needed to be trimmed on both sides to clear the chains. Could still use some heavy duty fender struts, especially on the rear. I'll probably make them if I can't find any.
  13. softride

    softride Member

    kustom kruiser

    I would be interested in seeing what you come up with for a gas tank I am going to need a 5 gallon for my jet bike project
  14. midlifecrisis

    midlifecrisis New Member

    gas tank

    the tank i'm working on is two cylinders, which will be strapped to the frame with leather belts for an old-time motorcycle look. my initial thought was to use pvc and paint it silver, and although i found conflicting opinions on whether gas would eat it away, the most reliable source indicated that the pvc itself can withstand gasoline, but the cement might dissolve. my plan was to use liquid gas tank liner to prevent that problem. however, when i went to home depot, they didn't have pvc in the 4" diameter i wanted, so i went with abs, which will definitely dissolve in the presence of gasoline. my new plan is to use fiberglass resin to coat the inside first, and then after it is cured, use liquid gas tank liner to add a second barrier to the gasoline. it may well fail, but i'm going to give it a shot anyway. i'll post pics of everything when i'm done.
  15. jsmithy

    jsmithy New Member

    Do you have any more pictures of you recent modifications?