Likearock's first Project - 70cc Dax + Skyliner

Discussion in 'Frame Mounted Engines' started by likearock111, Dec 13, 2007.

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  1. likearock111

    likearock111 Guest

    Hey, MBers!

    Well, the Schwinn Skyliner, Dax 70cc kit, and my McMaster-Carr order all came in, and more importantly, finals are over (!!!!), so I decided to start my very first motorized bike. I really appreciate everyone who posts to MB - without you guys, I never would have even started!

    So, tonight I tackled the engine mounts. I used the U-bolt/steel plate design that I saw on here somewhere before (thanks, whoever came up with it!) for the front mount. I figured I'd post a rough sketch in case anyone else is trying to do the same build and is interested (see diagram pic). I'm pretty sure I'm going to put some rubber or leather between the mounts and the frame, like some other people on MB have done. I bought all of my mount parts from McMaster-Carr for really cheap. Part #s are in the picture. My wife got pretty freaked out when she came down to the basement to see what the racket was and saw sparks shooting out as I cut the steel plate. :) She hadn't seen an angle grinder in action before, as she's a city girl. Lol. And the intake/exhaust openings are taped off in the pics so I wouldn't get any steel grit in there...

    I have a few questions (already?!). First of all, can someone who's done this before comment on whether the intake angle (and, as a result, the carb angle) is reasonable? I've read a few threads on this subject before, but it can't hurt to have a second opinion.

    Also, I've come to realize that my clutch lever arm (is this even what it's called?) seems to be positioned somewhat differently than other kits (even Dax kits). The arm seems to swing much farther out towards the left foot of the rider than with other engines I've seen on MB. I attached pictures of the arm in both of its extremes. Is this normal? At what point along this path does the clutch actually engage/disengage?

    Thanks for your help!


    Attached Files:

  2. mickey

    mickey Guest

    Hey, your front fork is on backwards.
  3. likearock111

    likearock111 Guest

    ROFL! good call. thanks!
  4. Scottm

    Scottm Guest

    That's pretty funny, the forks on backwards. That's something I would do.
    Anyhow here a helpful post by Augi. I had to search a while to find it.
    The clutch arm you have is like mine but different than the one on Augi's. I think they bent the end to give a more straight pull on the cable.
    It's kind of up to you to find that happy spot where it engages and releases properly. The adjuster screws on the clutch handle and on top of the motor where the cables end wil help you fine tune the adjustment.
    Hope that helps.
    Last edited by a moderator: Dec 14, 2007
  5. likearock111

    likearock111 Guest

    That's really helpful, Scottm! I've gotta admit... I also had no clue what the big-diameter spring was for, but cable heat protection makes complete sense. Thank you!
  6. Ghost0

    Ghost0 Guest

    Just a note on the clutch arm. Your photo that shows it closest to the center of the bike will be your starting point. Once the cable is installed, when you pull the clutch in, it will move the lever farther to the center of the bike and disengage the clutch. Hope this helps.
    Last edited by a moderator: Dec 14, 2007
  7. beast775

    beast775 Guest

    mount plate

    make sure your front motor mount is completely flat on the steel plate!the casing wont last long if its not,good luck!and have fun and take your time:smile:
  8. fetor56

    fetor56 Guest

    The carb angle seems fine....i've seen them at all sorts of wierd angles and never heard any complaints.
    The clutch arm is ok....when u thread the clutch cable through the arm it will take up most of the slack when secured....any remaining slack can be taken-up with the 2 adjusters.
    Also IF your clutch pressure seems excessive replace the inner steel cable(only) with a good quality stainless steel cable and grease it beforehand with a mixture if grease and graphite powder(the stuff used for padlocks/locks etc)
    This mixture can also be used for the intermeshing gears on the right hand side of your engine.

    One thing i would think about though is that U-bolt...don't do it up tooooo tight and possibly even put a steel sleeve between the U bolt and the frame.Might sound like overkill but if it was my bike it would give me peace of mind.
    Hasten slowly. :)
  9. likearock111

    likearock111 Guest

    Well, my car got vandalized earlier tonight while parked on the street. Ripped off the windshield wipers down low where they bolt on, used them to gouge a great big "X" in the hood, and broke off my left rear-view mirror. Some people can be real jerks sometimes. Just one more reason to get the heck out of Cleveland.

    Might not be working on the bike for a bit - my free time will prolly go to repairing car/filing insurance claims.

    Thank you all for the really helpful posts; I appreciate them greatly.

  10. mickey

    mickey Guest

    Bummer. Working on your bike will be therapeutic though.

    BTW, I think the Skyliner works well with the HT kit. Admittedly, I baby mine, rarely exceeding 24 mph, but the hubs never heat up even after riding 20 miles. The only thing I dislike is the narrowness of the stock handlebars and I've just been too cheap to buy a new swept back set.
  11. likearock111

    likearock111 Guest

    So I finally got some time to work on the bike tonight. I spun around the front fork (lol), attached the rear sprocket, and installed the chain. the HT "manual" that came with my kit was pretty sketchy, so I kind of did what made sense to me, but I'd love a bit of clarification.

    1) When I was trying to thread the chain around the drive gear, I ran into the problem that it wouldn't fit without rotating the drive gear. I used this tube-like wrench that came with the kit to spin the gear and thread the chain - is this OK to do without any lubrication on the piston? It seemed awfully hard to turn.

    2) I was under the impression that the position of the clutch arm would engage/disengage the drive gear from the piston's action, but it seemed that no matter what position the clutch arm was in, it was very very hard (basically impossible) to pedal the bike once the chain was attached to the drive gear. Is this the way it should be?

    3) How tight is too tight for the rear sprocket bolts/nuts? I ended up tightening them until the lock washers that came with the kit became flat (like normal washers). I know that this has a lot to do with the probability of breaking spokes - should I go for the side of over- or under-tightening?

    4) The included chain tensioner doesn't really rotate as I thought it should. I have the standard cheap-o version that basically has a teflon (I think) wheel bolted to a metal plate. I found that, because the bolt that fixes the height of the teflon wheel has to be tight in order to lock in the wheel height, the teflon wheel is prevented from spinning. Is this normal, or should I be worried? I know, I know... I should prolly just get a better tensioner. :)

    Thanks for all your help so far. Now I've got the tank, carb, and cables left... getting excited to ride this thing!

  12. SirJakesus

    SirJakesus Guest

    #1 you did good. You could have removed the spark plug to turn it easier since that would eliminate compression. At least you know you have a good engine.
    2 Sounds like the clutch isnt disengaging at all. You have to pull in pretty tight on the arm for the clutch to let go (search for some posts on this topic.) You should be lubing up some clutch arm pieces, a metal pin and ball bearing. Make sure the cover over the left side drive gear is on tight, if its loose the lever will never push the pin in enough to disengage the clutch.
    3 I did them the same way on mine and I had some spoke breakage. Only when I got a rim with thick spokes (12ga i think) did i cease to have spoke breakage problems. I think its best to keep the bolts as loose as possible in order to just keep the sprocket straight and stationary. I think the less tension on the spokes from the hardware pulling them outwards the better. But I may be wrong so read up :) Keep in mind too that I rode my motorized mountain bike HARD. I did a lot of dirt roads and uneven country roads aswell as lots of hard acceleration so the breakage may have just been my riding style.
    4 I would remove the roller from its axle and grease it. mine have always had a fair amount of in and out wiggle to them. sounds like somethings bound up so take it apart and check it out. It should roll freely without binding up on the bracket.

    You're lucky you found this place. When I was doing my first build a few years ago I only had skimpy directions to go by. If I had this resource I could have avoided a ton of problems. I think the people here have seen just about everything these happytimes can dish out. The more you read on this forum the more things you can catch before they become a problem. Good luck and enjoy the ride! Remember to baby her and she'll do so in return.
    Last edited by a moderator: Jan 16, 2008
  13. likearock111

    likearock111 Guest

    Thanks for the advice! I'll definitely try to fiddle with the clutch position more, and read up on what I should be greasing.
  14. mickey

    mickey Guest

    Beware of undertightening the sprocket bolts. I was paranoid about mine on the first build and broke all 9 trailing spokes on the same ride. If you overtighten, you will put a small bend in the spoke. I dont think thats any big deal for a stainless spoke. That little bend is noting compared to the violence they underwent when the end was bend 90 degrees at the factory. If you are so loose that the sprocket bolts can work on your spokes, you'll chew them up. Definitely tighten them up at least until the split washers are flat, as you did.

    The chain tensioner usually (always in my little experience) has a shoulder bolt. Make sure that it is correctly aligned with the slot in the bracket. Usually misalignment makes the roller too loose but that it the only thing there is to adjust on the tensioner that I can think of.

    Unless your bracket is bent, or the roller is touching, or trapped under, the top mounting bolt. :grin: It happens.

  15. likearock111

    likearock111 Guest

    Hey Mickey

    I just realized that you are the person I got the front engine mount idea from - thanks a ton! Also, I think I will start looking into getting 12ga spokes and be sure to check the ones I have for breakage regularly like the posts on this forum suggest.

    So, I have officially demonstrated my newbieness AGAIN. I had been thinking that the clutch arm was engaging/disengaging over the rotation that I showed in my previous photos. Now I understand what Ghost0 was talking about in his earlier post... the clutch engages/disengages as you push it even farther towards the center of the bike! I just didn't realize that there was such a strong opposing spring force on the clutch arm. Wow - probably wouldn't have ever figured that out if it weren't for this forum. Thanks, guys.
  16. likearock111

    likearock111 Guest

    Is there any danger in pushing your bike backwards when the clutch arm is in (engine disengaged)? I can't really think of a reason why it would be bad for the engine (but then I'm an engine noob), but there seems to be a "click, click, click" noise coming from the engine when I do, so I stopped.

    Put on chain tensioner, carb, throttle assembly, and clutch brake arm tonight... maybe it'll be done by this weekend!

    Oh, and the friction problems I had been having with the chain tensioner were because the teflon wheel can "pop" between two different positions along the length of the attachment bolt. One of these positions rubs against the metal plate, but the other doesn't. Thanks again for the help!
  17. mickey

    mickey Guest

    Are you sure the cut sides of the roller bolt are fitting in the slot on the bracket. You shouldn't have much space on the bolt for the roller to move in/out.
  18. likearock111

    likearock111 Guest

    WAAAAHHHHHOOOOOOOOOOOOOOOOOO!!! It WORKS! It is so sweet... just gotta remember to baby it :(. Even at 10:30pm in a parking lot, it was turning heads, lol. I had no idea it would be this cool.

    After about a half hour of riding, the chain tensioner bolt came loose and the chain came off, but it was an easy fix. Taught me to be sure about my nut/bolt tightness. I think I'm going to look into some LocTite

    THANK YOU ALL for all of the help and advice you have given me! Special thanks to Mickey for the design ideas and continuing help. Like I've said before, if it weren't for this forum, I wouldn't have even tried. Now I've gotta get one of those slick stickers to slap proudly on the side (and maybe even a shirt)!
  19. mickey

    mickey Guest

    Rock On!
  20. SirJakesus

    SirJakesus Guest

    Glad to hear its running for you! Remember to give it a go-over before you ride every time. At this stage you should check just about everything on the bike and motor until every things settled in. Make a tool kit too, nothing worse than breaking down and knowing all you needed was X tool to save you from a long walk home. Have fun be safe!