Magician Performance Improvement Project

[China Rider 27]

Intake PIX

[China Rider 27]

Intake Manifold and combustion chamber final PIX Exhaust

[China Rider 27]

Working on a Magician is not for the faint of heart. It is I believe one of the most difficult Chinese bikes to work on in many ways and certainly in the engine area, because it seems “poured into the frame.” Some of its likeable features, being small and compact, no wasted space, are also what makes it difficult to “mechanic”. Those issue became evident again when I tried to get the old head out to install the ported head. Just enough space to clear the cylinder studs and then it is a maneuvering proposition, but an engine head mounting bracket on the frame prevented the head from coming up enough to clear. I had to grind off a portion and took some off the head too to get it out. No small feat to get the new head in either but I did and got it fired up. First impressions, LOUD!

[JerryHawk250]

Nice job on the porting.

[China Rider 27]

Originally Posted by JerryHawk250

Nice job on the porting.

Thanks Jerry! When I look back on it I can't help but want to get back in there and take some more off there or cut some over here but I think restraint is the key! And it is an art, you will get better at with practice.

[JerryHawk250]

Originally Posted by China Rider 27

Thanks Jerry! When I look back on it I can't help but want to get back in there and take some more off there or cut some over here but I think restraint is the key! And it is an art, you will get better at with practice.

Yeah, it's not as hard as most people think it is. You just have to take your time at first. The next one goes some much quicker.

[China Rider 27]

I am wondering about that head gasket thick versus thin. I use 87 octane no ethanol. I have no access to 90 octane no ethanol. If you use that thin gasket and bump CR .5 and later advance the timing do you think you can get into a pinging knocking issue?

[Deckard_Cain]

Originally Posted by China Rider 27

I am wondering about that head gasket thick versus thin. I use 87 octane no ethanol. I have no access to 90 octane no ethanol. If you use that thin gasket and bump CR .5 and later advance the timing do you think you can get into a pinging knocking issue?

It's possible....

I have a ported head, using thin gasket and run 93 octane with up to 10% ethanol.. runs like a raped ape as they say.

[China Rider 27]

Headporting first results.

I need to finish some prior work on the PE 30 tuning before I get to the installation. On 6/8, I left off with the PE 30 at the last tune without the WOT runs. So they are:

6/14 (No changes in tune from 6/8) which are
Pilot 40
1 7/8 Mixture screw
Main 135
WOT 63 mph
Temp 61 degrees

Air pressure adjustment for tires, off idle hesitation re-appears, backfire 1X with high open throttle slide shutdown after acceleration

8/2 (No changes in tune from 6/8)
WOT 63mph
Temp 70 degrees
Hesitation just off idle when cold

I installed the ported head with a standard (thick) head gasket and torqued to 23 ft lbs four main bolts and 22 ft lbs outside bolt in two stages. This because I want to run non ethanol gas and what I have available is 87 octane and I am leery of pinging or knocking with compression increases. As such the comparison is closer to a stock factory head. I installed the PE 30 as it was with the 6/8/2020 tuning no adjustments made to idle, jets, or mixture screw. This setup should give a direct comparison to the stock head versus the ported head as this carburetor setup has been run on both with the same tuning. The carb started and idled pretty much as it did with the stock head. The results of two runs:

11/21 Head ported (same tune as above)
WOT 62 mph
Temp 49 degrees

11/27 Head Ported (same tune as above)
WOT 62 mph
Temp 51 degrees

Thoughts: Hmmm, I thought It would push the top speed up some by flowing more air but the GPS does not lie. No hesitations to indicate it was lean or issues on roll off. Maybe tuning will show some gain in the WOT. The mid-range was noticeably improved much smoother and it appeared to broaden the usable rpm range within any given gear. Almost like going down a couple 3 teeth on the rear sprocket or up on the front sprocket. Acceleration was also excellent. Pix of the stock head and ported head so a side by side comparison can be made.

[franque]

What gearing are you running, and what's the rear tire size? It could be you need less teeth in the back.

[China Rider 27]

Yes that really is the issue in terms of increasing significantly top speed with a Magician. It is a 428 17F and 45R. The problem with the Magician is you cannot obtain a lower rear sprocket because the design of the sprocket is limited to 45 teeth. Some have developed ways around it and I may too one day. The 16 inch rear tire also limits potential. Despite those limitations I thought there might be a small bump. I just took it out this afternoon to try it without the baffle. Sounds amazing. I wish I could upload a video of it but I don't have u tube account. I am not disappointed because it has increased engine efficiency in the power band. The result and pix of exhaust minus baffle.

PE 30 (slight idle adjustment otherwise tuning as above)

63 mph
Temp 53 degrees

[China Rider 27]

Here is a pix of the plug after the WOT run. No tuning adjustment looks worthwhile, granted a WOT plug chop might show some variation, but it appears to like the baffle removed and that light grey color in the exhaust says good mixture too. This PE 30 (28) continues to demonstrate a hesitation and hiccup just off idle on acceleration. It will cough, spit, then as you continue to move the throttle it takes off and no issues the other side. This day it continued to demonstrate rumbling on deceleration and the hiccups just off idle upon opening the throttle for a good 15 minutes into the ride and then cleared up. Given a rather chilly day, it appears almost a thermometer for the engine warming up. Such behavior in a carburetor would normally disqualify it for use, but it runs so well once you get it warmed up I tolerate its quirks. Maybe go up on the pilot jet sometime.

[Megadan]

It took me a while to get my pe30 really figured out. I ended up dropping the needle down 1 notch (2nd from top) and running a 38 pilot jet. That sorted out most of my throttle transition hiccups. With a 35 pilot and needle in the 3rd notch it tended to behave a bit like you describe.

[China Rider 27]

Originally Posted by Megadan

It took me a while to get my pe30 really figured out. I ended up dropping the needle down 1 notch (2nd from top) and running a 38 pilot jet. That sorted out most of my throttle transition hiccups. With a 35 pilot and needle in the 3rd notch it tended to behave a bit like you describe.

Good to know I'm not the only one. By 2nd from top you mean 2nd position as 1 through 5 going towards the needle tip to be sure? This inexpensive PE30 does not have an adjustable needle. I had a washer under it but it didn't seem to help. Gotta be some lean condition, rumbling on deceleration and it is just right off idle. But it idles great.

[Megadan]

Originally Posted by China Rider 27

Good to know I'm not the only one. By 2nd from top you mean 2nd position as 1 through 5 going towards the needle tip to be sure? This inexpensive PE30 does not have an adjustable needle. I had a washer under it but it didn't seem to help. Gotta be some lean condition, rumbling on deceleration and it is just right off idle. But it idles great.

Yes, I mean second from the top, or 4th from the tip. Basically the opposite of adding a washer.

Obviously there are variables that may make my settings not work for you, but I had a similar off idle hiccup just like you describe. My issue was a slightly too lean pilot jet transitioning to a slightly too rich needle. Once I moved the needle down to lean it out a little the stutter itself went away and the lean nature of the pilot jet came out more distinctly. Once I upped the pilot and got my mixture dialed in it ran like a.top.