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Old 01-28-2003, 11:28 AM
  #16  
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Originally posted by Brett
yeah that or the front bearing shims are too big and itsbinding on the seals ??????

i work at a hobbie shop and i do rember thatthe hpi need differnt shims for it ?????????
What are you trying to say or ask? Are you asking a question, cuz it's a statement with question marks?

Good point on the engine bearing idea. But if it was that wouldnt it "act up" from the start? Keep trying man, you'll find out the problem one of these days.
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Old 01-28-2003, 01:42 PM
  #17  
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Okay, I'm checking the clutch right now, and im noticing that the clutch bell is moving in and out.(i.e. Away and twards the the flywheel.) Maybe i just need another washer there to stop that?

Rob
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Old 01-28-2003, 01:56 PM
  #18  
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My clutch bell moves like that as well. Dosent hurt a thing as far as im conserned.
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Old 01-28-2003, 08:33 PM
  #19  
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Default Clutch-bell Spacing (washers)

Fiream;

The needle bearing on the clutch should not be brown in color. If it is, then it has probably been damaged from lack of lubrication.
This sound that you describe is EXACTLY the same sound that my Mini Bike's clutches used to make (back in the old days) when the clutch bushings needed oil. I remember it well and have had this happen to my HPI Nitro cars too.

The Washers on the clutch-bell just keep it from moving in and out. Too much movement can cause the teeth to grind into the plastic spurs and strip out a spur gear, though extremely rare. Just add a shim/washer to minimize the end-play.

Question; Does the Pull Starter Rope eject itself when the sound occurs? If so then your One-way bearing on your Pull Start needs Greasing/replacing (probably both).
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Old 01-28-2003, 08:56 PM
  #20  
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NO, no ejecttion of the pull-start...
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Old 01-29-2003, 02:02 AM
  #21  
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ok to see if its your 2 speed why dont u put your single back in?
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Old 01-31-2003, 07:11 PM
  #22  
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First of all Firearm this:
I have inspected the 2 speed many times and nothing seems to be wrong with it. I do know that when I first installed it that the gears riding on the bell housing were very tight even after I meshed the gears with a piece of thin plastic. After that I oiled the gears and they start to loosen up. but I can tell you it is a 2 speed problem, if I spin the gear of the 2 speed in reverse they will make the squeeking noise, it's almost as the inner clutch is binding... I'm really puzzled as to whats wrong and I don't want to end up buying another $90 2 speed....

Rob

When you installed the two speed bell housing and the part that get's screwed to the shaft you might have tightened them together too much. Loosen the set screw that holds the shift mechinism? and move it a touch off the bell housing bearing. If you tighten them together to tightly there is binding.
So give it a little play, OK.

Now for this:

Okay, I'm checking the clutch right now, and im noticing that the clutch bell is moving in and out.(i.e. Away and twards the the flywheel.) Maybe i just need another washer there to stop that?

Rob

You need a little play but not a whole lot. A washer will do. And also make sure both gears are aligned up with one and another.

Another question is do you have the heavy duty first gear adapter or does the one way simply press into the first gear?


You have to keep up on the maintence on both the two speed and the clutchbell. Keep them clean and oiled/greased.
I grease the clutch bell needle bearings with white lithium grease. It seems to last a few weeks. And I have not had a problem with them at all.
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Old 01-31-2003, 07:26 PM
  #23  
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Originally posted by Dear HPI
but I can tell you it is a 2 speed problem, if I spin the gear of the 2 speed in reverse they will make the squeeking noise, it's almost as the inner clutch is binding... I'm really puzzled as to whats wrong and I don't want to end up buying another $90 2 speed....
I'm really amazed at people still insisting that this is a 2-speed problem. Surely if the car is sitting stationary at the start line the clutch shouldn't be engaged so how can the 2-speed be doing anything to stall the engine. If the screech is coming from the 2-speed before the engine stalls it surely tells you that something is not right with either the clutch or the engines settings.

If the car is sitting stationary and the clutch is engaging then surely this will tell you that the idle is far too high on the engine. The one way bearing on the 2-speed might be bad but that is nothing new for HPI anyway and it might be causing the engine to stall once the clutch is engaged but it cant directly effect the engine otherwise.

Use some common sense
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Old 01-31-2003, 07:54 PM
  #24  
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Yes, When the car is sitting at idle and if there is tension between the first and second gears. This would make a binding onto the clutchbell. Do you see what I mean? It would be like having the brake on all the time. So if the clutch is trying to engage into this binding of the gears then what is it going to do??

Stall.

Even raising the idle would not help either. because it would bind still.

If the clutch bell spins freely then it can not be the problem.

True, the tuning of the motor would make the motor stall after 5-10 seconds but not the clutch...If the motor is stalling sitting on the track, Will the car will idle for more than that if held in the air??? Hmmmm. Binding of the gears then maybe? If it was the needle bearings wouldn't a drop or two of oil stop it?

Hey we all got our own opinions. Are you racing an HPI or did you have one a while ago too. I am a half a lap off the best car's at the track. Sure they are running foam I am not. But it is like a Pro pitcher in baseball some days he is untouchable and the next he get's knocked out in the first inning. I will settle for second all the time, I haven't payed alot and I am having fun.

LTR... Long Time Racer.
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Old 01-31-2003, 08:00 PM
  #25  
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Originally posted by modellor
I'm really amazed at people still insisting that this is a 2-speed problem. Surely if the car is sitting stationary at the start line the clutch shouldn't be engaged so how can the 2-speed be doing anything to stall the engine. If the screech is coming from the 2-speed before the engine stalls it surely tells you that something is not right with either the clutch or the engines settings.

If the car is sitting stationary and the clutch is engaging then surely this will tell you that the idle is far too high on the engine. The one way bearing on the 2-speed might be bad but that is nothing new for HPI anyway and it might be causing the engine to stall once the clutch is engaged but it cant directly effect the engine otherwise.

Use some common sense
modellor,

Sometimes, you cannot use "common sense" to explain HPI stuff !
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Old 01-31-2003, 08:02 PM
  #26  
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Its apparent you dont fully understand how a clutch works. Regardless of how tight the gearbox is and how tightly meshed the gearbox and clutch is it still cant stall the engine if the clutch isnt engaged.

As for a clutch dragging. It can stall an engine if the RPM is not high enough but then again if the clutch is not binding and can slide forwards and backwards then the engine is idling too high making the clutch engage at idle. This WILL stall the engine.

I dont have an HPI but I do work on one for one of my proteges. I know how crap the HPI gearboxes are but it aint the culprit.

And it wouldn't matter if the car is on the ground or in the air. If the clutch is dragging it will stall the engine regardless if their is not enough rpm to turn the wheels.
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Old 01-31-2003, 08:03 PM
  #27  
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Yep, You have to experience it.
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Old 01-31-2003, 08:04 PM
  #28  
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Originally posted by Manticore
modellor,

Sometimes, you cannot use "common sense" to explain HPI stuff !
Thats a good point Manticore. Should have thought about that.
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Old 01-31-2003, 08:11 PM
  #29  
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What is there to understand centrifugal force and friction, Duh.

It doesn't take a degree to get that. What I am saying if it was the clutch it wouldn't idle at all. So I am looking farther into the picture.

go forward move ahead. Not if there is binding????
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Old 01-31-2003, 08:25 PM
  #30  
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Ok. We'll put this in Kindergarten language for you to grasp what is actually happening.

The car is sitting stationary at the start line and the engine is stalling after a few seconds.

The gearbox is tight and binding (doesnt matter yet).

The clutch must be engaged at real low RPM for the engine to stall. This tells me that the RPM is too high at idle.

The car is trying to move forward at really low rpm which is quite difficult for it to do in the first place due to weight and laws of physics.

Now because the gearbox is binding the car cant move forward and so the clutch stalls the engine.

Simple solution is to lower the idle RPM and go and buy a decent non-HPI one way bearing to suit that will work properly.
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