Engine swap: 50cc to 150cc By chroniktheory (Read 3,209 times)

[chroniktheory]

Alright, as some of you may or may not have seen in my previous post I have been in the process of replacing a TaoTao ATM50-A 50cc 1P39QMB with a 150cc 157QMB. Well success! It's done. Pour the champagne, cut the cake, let's ride.

...Yeah not so much.

I have mounted the engine (welded engine hanging bracket directly to frame, wasn't so bad) and replaced everything mechanically needed to make it road worthy. Upon finishing I wired everything back up and was ready to ride my kick-ass new toy. Well it wouldn't turn over; or it would turn over but barely. A slow thwop if you will. Now it was having this problem BEFORE the engine swap as well. I attributed it to either bad battery or cold weather as it would fire right up once warm. Well now it has a brand new battery and I've tried starting indoors. Here are the things I've replaced/checked:

- All grounds. Good to go.
- Replaced Rectifier.
- New CDI
- Removed starter motor and did a solo jump. Turns just fine.
- Removed wiring harness and protecting loom. If it's bad I can't tell.
- Sacrificed a lamb to the Scooter God.

Nothing has changed after doing all of these. I'm at my wit's end here. Any ideas?

[alleyoop]

Great, how about some pictures of your 150 mounts on the 50cc frame so others may know how to do it. As far as not turning over try turning the motor over by hand and see if it comes up to compression stroke and has some resistance and then none and do this a couple of times. Try jumping the SOLENOID and see if it spins your starter or just a wimp RRR. Then I will say your battery is not charged and is weak, if you have a multi meter set it on DC and see how many volts it shows it has. Also what size battery did you get?
Alleyoop

[chroniktheory]

Sure thing! Will try to accommodate tomorrow! (No promises as it's new years and I'm getting inebriated) I will also explain that process with the pictures. What is the best way to get pictures on here from a cell phone? (I haven't taken pictures and it is a smart phone) Also should I make a new thread for that or just post in this thread?

As an answer:

 I have jumped from the solenoid (knew I forgot to list something) and got nothing (What is RRR?). As far as battery, I bought a 12v/7Ah which seemed typical of other models of same size. I do not have a multimeter but my charger has that setting built in. Readings are nominal captain. Engine does turn as according to a normal 4 stroke.

[alleyoop]

You can post on this thread Maybe just RENAME the thread Title to 50cc to 150cc Swap.
to post pictures on the REPLAY see the PIC ICON BELOW the I use that. If not then you can load the pic using PICTUREPUSH then copy the link and post it here.
Alleyoop

You can use push picture to put up pictures here it is easy and free:

picturepush.com/host.php?image=10075950

1. Click on the BLUE UPLOAD another image
2. Click on BROWSE
3. That will display your computer directories
4. click on where your picture is at
5. Click on your picture and click on OPEN and it will load it
6. Then scroll down to the box where it says640*480
7. Click on the 2nd entry in those links -- it will turn blue
8. Right click and click copy
9. Come here and right click and paste it in your post.

[chroniktheory]

Awesome. Thanks. Last question I think... How do I rename the thread?

[alleyoop]

To rename the thread just come on the post and then EDIT the thread name. It is your thread so you can rename if if you can't I can do it for you.

Ok so if you jumped the SOLENOID and it did not spin the starter YOU may not have it connected correctly here is the SOLENOID and how it should be connected. Now you should have a GROUND wire from the NEG POST Of the battery to a GOOD GROUND on the FRAME. Then another GROUND from the FRAME to one of the VALVE COVER BOLTS.
Alleyoop

[chroniktheory]

Alright got it. Didn't see that I could edit the title from the initial post's EDIT options. Thank you!

As for that I THINK everything is good to go but now I'm second guessing whether or not I have a ground wire coming from my solenoid. I shall have to check tomorrow! I am going to feel like a jackass if it isn't... That poor little lamb.

[alleyoop]

No there is no ground wire from the SOLENOID.
The SOLENOID you hook the THICK POSTIVE RED CABLE from the BATTERY to one of the SOLENOID POSTS. The OTHER post on the SOLENOID goes to the STARTER.

The only ground wires is ONE FROM THE NEGATIVE POST OF THE BATTERY to the FRAME. And then another GROUND WIRE TO THE MOTOR. Of course you have all the other green Ground wires that should be grounded to the FRAME.
Alleyoop

[chroniktheory]

Aha, that's where the confusion was coming from. For some reason my mind transposed the word solenoid and battery. And my battery ground is on my rocker/head cover. Also, I went digging through my phone and apparently I did take pictures and I also apparently have a photobucket account. Who knew? So I'm getting on that now.

[alleyoop]

Ok, Take the Ground wire from the battery on the valve cover and GROUND that to the FRAME then take another wire put it on the same bolt on the frame that the BATTERY GROUND is NOW GROUNDED TO and put that on the VALVE COVER BOLT.
Alleyoop

[chroniktheory]

Ok for starters I had no idea that 50cc engine and 150cc engines mounted differently. Woops. That being said this is how I made it work. Upon this realization I did some research on the subject and found that 150cc's have there own mounting bracket or hanger. After looking at them online I purchased one in hopes of making my brackets to attach them to. Hanger shown below

Once I received stated bracket I came to the conclusion that making proper brackets for this hanger was a little too complicated for me (might be best for a more experienced machinist) as this is the proper way they attach.



What I decided to do as it was too complicated and the mount was too wide from my small frame was cut the ends off leaving only the hollow tubing of the mount. (Make sure you measure and center while mount is attached to motor for this step) Using an old center stand I had I cut off the mounting ears from that, cut and bent them to fit my mount and it ended up looking like so...

[chroniktheory]

Top view:



Welds after bedding and griding:



Little paint:



Whole mount painted and cleaned up:



Engine on mount:



Rear end:



Her stance (plus bonus 05' Longbo LB150T-12):

[chroniktheory]

Ok so battery ground to frame and secondary ground (from frame ground) to valve cover? May I ask why? Wiring ain't my digs if you couldn't tell.

[alleyoop]

Yes, if the motor is NOT grounded the Spark plug will NOT fire. Also the battery ground, grounds the battery so all accessories using the battery will work. Also the starter has only one connector and that is for the LIVE WIRE from the SOLENOID and the starters GROUND is the MOTOR.


Good job on the pictures of how you mounted the 150 on the 50 frame.
Alleyoop

[chroniktheory]

I understand the basics wiring/continuous circuitry and as stated before I have checked all of my grounds. My battery is grounded to the engine which is is bolted to my frame. That is ground. That is the purest sense of the term ground. I have spark which confirms that. And all my accessories work. Unless I'm missing something this thing is grounded. Please correct me if I'm wrong.