Too hot?

ishman

Member
May 19, 2014
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Michigan
I just switched my Townie to 4 stroke power, and by the way 5 stars to Thomas and the gang at Motorized Bicycle USA for getting my 53CC Huasheng Engine to me fast.
This is a sweet little engine, it started on the first pull and and it has awarded me with a ride that is much smoother (not so hard on the 55 year old "taint"). Because of frame geometry I could not use the stock carb, I had to order an angled intake manifold from FFV8 , (Brad makes good stuff) and had to use my NT carb from my 66cc 2 stroke engine. Now, I checked the size of the main jet in the 4S carb and it was .021", (#75 drill size). In the NT carb, I started with a main jet which was .024" or #73 drill, jet is #62. I have since switched to a #67 main jet. It seems to run pretty good but it is getting hot enough to get the pipe wrap smoking after a short ride on and off the throttle. I have a brand new BBR Longshot pipe on the bike that looks sweet, but is LOUD! So I bought an 8" can opener baffle for it. Im sure it is adding to the heat situation. I am just wondering if it is normal for that pipe wrap material to smoke like that at first. I have attached pictures of the pipe, plug & baffle.

Thanks,

Ishman usflg
 

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FFV8

New Member
Oct 29, 2013
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Spring Valley NV
Fatten it up a little & see how it runs - just raise the needle a notch or two.

4 strokes run hotter on the exhaust pipe than two strokes.

Pipe wrap often smokes a little the first few times it gets hot too.

.
 

ishman

Member
May 19, 2014
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Michigan
I will raise the needle it's right in the middle at the moment. I was kind of hoping there was something in that wrap that was burning out of it .

FFV8: here are some pics on how the angle manifold helped out big time. Couldnt have got it in there with out it.
 

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Slogger

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Sep 8, 2014
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nohio
I'd keep fattening it up until it ran poorly, then back off one jet size (or needle notch, whichever) because lean running will quickly ruin your new engine.
 

Tony01

Well-Known Member
Nov 28, 2012
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I'd keep fattening it up until it ran poorly, then back off one jet size (or needle notch, whichever) because lean running will quickly ruin your new engine.
No, better to run it slightly lean than slightly rich, too rich or lean is bad. When it's too rich you will get excessive carbon buildup and will start seeing a lot of blowby and gas-contaminated oil. I've destroyed one engine this way thinking rich was ok. Lean it up till it's too lean then back it off.

The heat wrap will stop burning at some point though sometimes it seems it never stops. I've heard it's better when applied wet.
 

ishman

Member
May 19, 2014
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Michigan
Well at least I wont be so freaked, if I see the wrap smoking again. The motor had no top ened on the #62 jet, and the plug was white on one side. I richened it to a #67 jet and the motor woke right up.
I will give it a few more miles and see if the smoke stops and keep an eye on the plug for exsessive carbon. The picture of the plug was taken after the switch to the #67 jet.

Ishman
usflg
 
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KCvale

Well-Known Member
Feb 28, 2010
3,967
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Phoenix,AZ
I suggest you back up a couple steps before jetting...
Pop the silver cover on top and adjust the rocker arms.
0.004" intake
0.006" exhaust
Intake in back, exhaust in front.

Just pull the start until both valves are completely closed and adjust the gap between the actual valve and the rocker arm.
It's tricky to do, but worth it if it is off by much.

Then get yourself an NGK 7544 (CR7HIX) Iridium spark plug, it's a bit longer so you get a bit more compression + a really great spark that lasts decades.
Pre-gaped as well, the plugs have a cardboard protective ring over the end.

Starting there I don't have any HS engines problems including dinking with carb jets.
Just a tip ;-}
 

ishman

Member
May 19, 2014
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Michigan
OK , valve lash it is. Im used to doing it on my Fairlane FE motor, should be a breeze. I was going to do a search tonight for a better plug, so thanks for the timely info on the NGK Iridium job.
Got to ride it yesterday for the first time in a few days because of rain. It was smoking and leaving lots of carbon on the plug and had no top end at all, so Im going back to the jet I started with and do the valves and change the plug. We'll see where we are at then.

Ishman
usflg
 

KCvale

Well-Known Member
Feb 28, 2010
3,967
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Phoenix,AZ
OK , valve lash it is. Im used to doing it on my Fairlane FE motor, should be a breeze. I was going to do a search tonight for a better plug, so thanks for the timely info on the NGK Iridium job.
Got to ride it yesterday for the first time in a few days because of rain. It was smoking and leaving lots of carbon on the plug and had no top end at all, so Im going back to the jet I started with and do the valves and change the plug. We'll see where we are at then.

Ishman
usflg
Good plan, just be sure to check what the valve lash is first for reference, and then see what fixes what.

I think you'll be surprised with the difference just those couple of things make.

A couple of others are get rid of that 'box exhaust', even a 2-stroke pipe is less restrictive, and while you are at it remove that silver shield around the cylinder fins!

These engines were deigned to be stationary and the shield was used to blow air from the engine fan to cool it.
You have motion to cool it better now.



Other than those 4 there just isn't much more you can do, but if you can do 40mph with gears like that build there just isn't much need.



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ishman

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May 19, 2014
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Michigan
Yeah, if you look at the pictures I uploade and read previous posts, I have already installed a Longshot pipe and removed all shroud material, metal and plastic, The only thing left on the engine is the pull starter.
I really dont care to do 30mph for long periods on a bike, but I do want the engine to perform as good as it can (which it isnt doing at the moment) and be as reliable as possible.

Thanks for the sharing of your knowlage.

Ishman
usflg
 

KCvale

Well-Known Member
Feb 28, 2010
3,967
52
48
Phoenix,AZ
I just switched my Townie to 4 stroke power, and by the way 5 stars to Thomas and the gang at Motorized Bicycle USA for getting my 53CC Huasheng Engine to me fast.
This is a sweet little engine, it started on the first pull and and it has awarded me with a ride that is much smoother (not so hard on the 55 year old "taint").
Ya, I like the 144F's better than the 142F's, it's only 4cc lager but I can feel it, especially with a couple mods and gears.

I have used the off-set Z intake with an NT carb, it's not as good as stock once you get into the only performance mods you can do.

1. Replace the stock plug with an NGK 7544 (CR7HIX) Iridium plug.
It doesn't just spark better, it is tad bit longer to increase compression, comes per-gapped, and will outlast the engine.

2. Put ANY other exhaust on other than the stock box exhaust.
I just use a 2-stroke pipes they bolt right on.
Sure, they have a little back pressure, but less than the stock box.

3. An air cleaner that lets more air in and still handles the engine vent without a catch can.



Bummer you need to use a Z intake and NT but this may give you some insight into your next frame choice.





These little ~50cc 4-stroke engines can put out enough power to do whatever you need from climbing a step hill @20mph to hammer down to 40mph+ on the flats.
That's an internal 5-speed, and gears change everything.

I just have to smile at these guys that want want to drop a 212cc Predator engine on bicycle, I can pretty much ride with them with 1/4 of the power, and gears.





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ishman

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May 19, 2014
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Michigan
Yeah, originally I bought the Townie just to pedal around, I liked the flat foot frame geometry. I still like the bike, it is comfortable, but I have vascular disease and I cant pedal for very long distances and having a "motor" bike apeeled to me in a big way.
I am not using the Z bend intake, although I have one that I originally bought for my 2 stroke, what a performance killer. I am using FFV8's angled intake. last night in my frustration with the NT carb, I put on a Runtong SHA clone with a #78 jet (this is a setup I have read that others have been using) it does perform "better" than the NT, but this motor will not reach top end, it just hesitates. I reset the valve lash to correct setings, the intake was at .003" and the exhaust was at .008", I also installed the NGK Iridium plug.
What are you guys using for a tachometer? I would like to know what RPM I am getting.

Ishman
usflg
 

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sbest

Member
Nov 3, 2015
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OK , valve lash it is. Im used to doing it on my Fairlane FE motor, should be a breeze. <SOME SNIPPED>
Ishman
usflg
Hydraulic or mechanical? FE's were not all that bad. Some Honda bikes were a nightmare having to put a feeler gauge, 8mm and 4mm wrench into a tiny hole under the gas tank every 1000 miles. Like tuning spokes, I used just rely on the click noise for gap. "Kik-kik" too tight, "CLACK-CLACK" too loose, "click-click" just right.

Best car I ever had was a 1970 Torino(Fairlane) with the 351C 4v. Big and comfy but light and went like ****. Wide enough to handle well. Loved that car, but all good things come to an end. It rusted and got sold for $350 without motor. Motor went into this Maverick with a "Q" code camshaft, Torker intake and of course custom headers.



It was fun, but I still liked the Fairlane chassis.

Steve
 

ishman

Member
May 19, 2014
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Michigan
66 Fairlane GTA (390), was the purple camshaft hydraulic and I switched to solid lifter with a cam grind from an FE specialist - Blue Thunder PI intake/Demon carb etc, I love all cars but my dad was a Ford man and his dad and my God father worked for Henry, so I guess I have a slight prejudice. [added picture of the Erson rockers, easy to adj.]

Damn bike is still not running right.


Ishman
usflg
 

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sbest

Member
Nov 3, 2015
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Nova Scotia
Sweet! I failed my first driving test in my uncle's 67 2 door Fairlane much like yours. I spun the tires a couple times leaving lights and stop signs. Took my second test successfully in a VW...

Back to thread. I've had some luck with Trail Tech TTO temp gauges for air cooled engines. Gives you some idea where you are trending and the effect of jetting on temp.
 

ishman

Member
May 19, 2014
55
0
6
Michigan
OK spent the last 2 days finagaling this motor to fit in this frame with the stock carb on it and, voila! Perfect running engine. Have not checked temps or rpm's yet, but the wrap on the headder has stopped smoking as a few of you remarked it probably would in time. My wireless speedo took a crap so I dont know what speed Im getting but my butt is telling me under 30 (26" wheels - 9t to 44t sprockets - 250lb dude). For now Im happy. I say this because like most of y'all I can never leave well enough alone. I just cant believe I could not get that NT carb to work, it worked fine on the 2 stroker.

Ishman
usflg