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Old 01-30-2020, 05:32 PM
Shax90 Shax90 is offline
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Default Cant get torque converter to engage

Hey guys I just got my bike running but I've got a problem. I cant get my converter to engage and I already moved the spring to the easier hole. Im only hitting about 25 and I'd like to at least get 35. I used a calculator and Its says with my wheel size and ratio I'm only hitting about 2400 rpm it activates when i have the wheel lifted so i guess i need to upgrade the engine I upgraded the air intake and out a zip tie on one of the springs on the throttle which gave me a tad more speed. I upgraded the jet as well however it is the stock carb. Btw this is on a predator 212. I planned in using a 90 1" emt electrical conduit for a homemade muffler bevause I have the stock one on(if any other suggestions on muffler that would give better performance let me know). Any ideas? I'll drop some pictures below if you need more let me know and I'll post as soon as possible.
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Old 01-30-2020, 05:39 PM
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Here they are
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20200130_191643.jpg   20200130_191613.jpg  

20200130_191706.jpg   20200130_191654.jpg  

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Old 01-31-2020, 07:40 AM
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Uh, zip ties on the throttle spring are never a good idea. That will let the engine rev to valve float (around 5200 rpm), however at anywhere over 4700 or 4800 I believe, you run the risk of the governor wheel flying apart inside the engine. Then the metal weights can lodge themselves between the cam and crank gears, or worse, between the piston and cylinder.

And what're your rear and front sprocket tooth count, and what size tires are those? I'd guess they're in the neighborhood of 26". With this problem it's more about gearing than hp.

Also, what bike is that?
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Old 01-31-2020, 08:27 AM
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What jet did you put in it? It may be too rich on the top end and not let it rev.
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Old 01-31-2020, 08:34 AM
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with both of these guys.

DON'T bypass the governor, you need to open it up and remove the governor gear.

Most of the time, I've found when an engine is mistuned, too rich will make it act up at idle, but will let it rev all the way out. Usually it's too lean that keeps it from revving all they way out.

One of my small engine repair books says that when it's too rich, it'll run rough all over the throttle range, but if it's too lean, it won't rev.
And just to throw it out there, another book I read showed that power drops off drastically when it's too lean, but power dropped off slowly when it's too rich. So better to leave it a tad rich.
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Old 01-31-2020, 08:47 AM
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Awlays best to take out the plastic gear if you want to bypass the governer

I know you had too, but the tensioner should be on the slack side of the chain, so lots of force is being applied directly to the tensioner sprocket every time you hit the gas , does it get hot after riding?
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Old 01-31-2020, 09:24 AM
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Quote:
Originally Posted by karl View Post
Awlays best to take out the plastic gear if you want to bypass the governer

I know you had too, but the tensioner should be on the slack side of the chain, so lots of force is being applied directly to the tensioner sprocket every time you hit the gas , does it get hot after riding?
No it hasn't gotten too hot yet but to he honest I've only rode for about 15 minutes. And ya I was getting to taking it out but someone said to out a zip tie on there and it would be fine for now. And theres actually two sprockets to bring the chain around the frame it's not ideal but that's what I had to do

---------- Post added at 11:17 AM ---------- Previous post was at 11:14 AM ----------

Quote:
Originally Posted by Flyinhillbilly View Post
What jet did you put in it? It may be too rich on the top end and not let it rev.
.038, it came with the air intake upgrade.

---------- Post added at 11:18 AM ---------- Previous post was at 11:17 AM ----------

Quote:
Originally Posted by JTSpeedDemon View Post
with both of these guys.

DON'T bypass the governor, you need to open it up and remove the governor gear.

Most of the time, I've found when an engine is mistuned, too rich will make it act up at idle, but will let it rev all the way out. Usually it's too lean that keeps it from revving all they way out.

One of my small engine repair books says that when it's too rich, it'll run rough all over the throttle range, but if it's too lean, it won't rev.
And just to throw it out there, another book I read showed that power drops off drastically when it's too lean, but power dropped off slowly when it's too rich. So better to leave it a tad rich.
What would you suggest trying? Beside taking out the governor instead of bypassing. Which I will be doing

---------- Post added at 11:22 AM ---------- Previous post was at 11:18 AM ----------

Quote:
Originally Posted by J.S.@SMS View Post
Uh, zip ties on the throttle spring are never a good idea. That will let the engine rev to valve float (around 5200 rpm), however at anywhere over 4700 or 4800 I believe, you run the risk of the governor wheel flying apart inside the engine. Then the metal weights can lodge themselves between the cam and crank gears, or worse, between the piston and cylinder.

And what're your rear and front sprocket tooth count, and what size tires are those? I'd guess they're in the neighborhood of 26". With this problem it's more about gearing than hp.

Also, what bike is that?
Ill be taking it out soon but rear 80 front 12 it was supposed to be 10 because I wanted 8:1 and the TC I got said it came with #35 10 and 12 tooth drive sprockets but the 10 wasn't 35 so I had to use the 12 and yes 26. Also I have no clue what the bike was I bought the wheels and frame off some dude on letgo for cheap

---------- Post added at 11:24 AM ---------- Previous post was at 11:22 AM ----------

After I remove the governor and add the muffler and it still doesn't work should I maybe drill a new hole in the TC.?
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Old 01-31-2020, 09:45 AM
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Put the bike on a stand and rev out the engine. Check to make sure the TC sheaves are moving all the way. I have a feeling the TC is staying in "low gear" and not letting you reach top speed.

You haven't messed around with pulley orientation, have you?
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Old 01-31-2020, 01:16 PM
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Quote:
Originally Posted by JTSpeedDemon View Post
Put the bike on a stand and rev out the engine. Check to make sure the TC sheaves are moving all the way. I have a feeling the TC is staying in "low gear" and not letting you reach top speed.

You haven't messed around with pulley orientation, have you?
I have and it does open up and if pulley orientation you mean moving the spring to the other hole yes i have
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Old 01-31-2020, 01:35 PM
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No, I mean flipping the pulley around to turn the other direction. Have you done that? Because 30 series tend not to like that.

---------- Post added at 02:35 PM ---------- Previous post was at 02:35 PM ----------

Oh, what's your gearing and tire diameter? It may be too high.
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Old 01-31-2020, 03:58 PM
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Needs a bigger sprocket
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Old 01-31-2020, 05:45 PM
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Quote:
Originally Posted by JTSpeedDemon View Post
No, I mean flipping the pulley around to turn the other direction. Have you done that? Because 30 series tend not to like that.

---------- Post added at 02:35 PM ---------- Previous post was at 02:35 PM ----------

Oh, what's your gearing and tire diameter? It may be too high.
No I have not it came partly assembled already and I watched a couple videos to make sure I did it correctly and it should have been 8:1 but they sent me an incorrect drive gear so it's a 12 tooth to an 80 instead of 10 to an 80 and diameter is 26"
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Old 02-01-2020, 09:18 AM
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According to the DIYGK speed calculator, 2400 RPM with that gearing will get you 28 MPH.
3600 RPM should net 42 MPH.

With a 10T sprocket, 2400 RPM will net 23 MPH, and 3600 RPM will be 35 MPH.
Is it a genuine Comet TC or a Chinese clone? I believe Comets engage at a higher RPM.
Don't drill more holes.

The problem I'm seeing here is that 2200 RPM is torque converter engagement, and at that RPM, with either gearing, it wants to do over 20 MPH, so the belt is slipping all that time while accelerating to that speed. Although that's not factoring in the ~20% overdrive the TC provides, but that only brings the engagement speed down to about ~18 MPH.

In short, it seems your gearing is too high and HP too low. Get that 10T sprocket on there and see how it does. If it's still too high, you may need a jackshaft.
Or of course you can upgrade the engine to make more HP.
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