[agdodge4x4]

I have a 1986 Fourtrax TRX200SX. I just got it back up and running after a family member gave it to me. It runs awesome. However, if you turn it off after riding, and its in Neutral, something continues to spin down for at least 10 seconds....I read online it could be the one way bearing. I cannot locate a means of testing this before disassembly and replacement. Also, in my manual it says to remove the right side Crankcase cover to make the repair....the noise I hear I swear is on the left side crank case pull starter area. I have no clue what it could be though. If you let it spin down and then put it in gear, the noise immediately stops. I have no issues with the starter or shifting. I'm wondering what it is.

I have the right side cover off to change oil and check filters. All is well there. You can only spin the clutch wheels in one direction. So...what is the noise Im hearing at shutdown?

 

[sabre54]

Pretty sure its the one way bearing.

 

[agdodge4x4]

Where is it located? I took the right side cover off today to inspect the oil screen, the clutches in there only turn one way. I can't get them to turn the other.

 

[retro]

I don't have the service manual for the 200sx... but it makes sense to me for that one-way roller to be located under the centrifugal clutch. The manual should explain what you'll need to get that centrifugal hub off and the procedure to change out the roller clutch.

 

[agdodge4x4]

Yeah...thats what I was looking at. The bearing is where you say it is, and I spun the outside of that thing and it only turns one way. It 'catches' the other way, immediately, no hesitation. That doesn't seem like a one way bearing issue.

Is there anything else that affects the 'free wheel' of the machine when going down hill? I guess I don't understand how it CANT free wheel down hill since the clutch is completely disengaged when idling.

 

[retro]

The one-way roller set can work fine in your hand, but fail under engine load... so there is no way to test the roller set except for pushing the machine while idling, or coasting the machine down hills while idling.

The one-way roller clutch set works to provide engine braking because of its location behind the centrifugal clutch... it becomes active (engaged) when the centrifugal clutch drum RPM exceeds the centrifugal clutch hub RPMs.

Once you have it all apart you'll be able to see how it fails... the rollers can get flat-spotted and worn due to them sliding in the drum ways (rather than rotating normally) and the roller preload springs can become worn out, broken, or sacked... leaving them too short to be effective.

 

[agdodge4x4]

THAT is the explanation I was looking for. Thank you very much for that. I'm sorry I made you go through that, but I am the kind of guy that needs to know HOW something works and WHY my diagnoses didn't point to the answer I already knew. I know...that's dumb...but now I understand.

Can you verify that we are talking about Part #29 in this IPL:

1986 Honda TRX200SX A CLUTCH | Babbitts Honda Partshouse

This is the failed part?

So..while using it today, it DOES engine brake...but not all the time. You have to either be IN the gear before descending a hill OR goose it while going downhill and it will engage. So...I guess its failed, but not all the way, yes?

 

[retro]

THAT is the explanation I was looking for. Thank you very much for that. I'm sorry I made you go through that, but I am the kind of guy that needs to know HOW something works and WHY my diagnoses didn't point to the answer I already knew. I know...that's dumb...but now I understand.

No need to apologize for anything... I'm posting here regularly cause I want to help others solve their own problems, becoming less reliant on the parasite class (least like them = independent opposites = breakaway humans) while doing so! Its fun and rewarding for all involved and its an opportunity to learn from others experiences, which eventually serve to benefit us all as we continue to share. So its not a dumb question, its intelligent use of time and resources!

Just for the record... I need to understand everything about a problem or a device too... how it works... else I'll buy no ones advice on what to do to solve for it. Glad you're that way too!

Can you verify that we are talking about Part #29 in this IPL:

1986 Honda TRX200SX A CLUTCH | Babbitts Honda Partshouse

This is the failed part?

Yep, thats the one-way roller set. Notice that the centrifugal drum provides the raceway for it. So that drum accounts for half of the roller bearing assembly.

So..while using it today, it DOES engine brake...but not all the time. You have to either be IN the gear before descending a hill OR goose it while going downhill and it will engage. So...I guess its failed, but not all the way, yes?

Yes perhaps its on its last legs... gotta look at it to be sure. If you take the clutch apart to get eyeballs on that roller assembly, check the crankshaft main bearing for any excessive play (endplay too) 'cause a loose bearing on the crank can cause the roller to intermittently fail to engage and/or fail to hold engagement.

 

[agdodge4x4]

How do I check the crank main bearing? Just wiggle it around for vertical and horizontal movement? Im kinda scared what I'll find because there is some rattly noise in that area when your just kinda just rolling at light throttle.

 

[retro]

Once you have it all apart you'll be able to see how it fails... the rollers can get flat-spotted and worn due to them sliding in the drum ways (rather than rotating normally) and the roller preload springs can become worn out, broken, or sacked... leaving them too short to be effective.

This statement may be incorrect, sorry about that. The one-way roller clutch in your motor may be a springless design... if that is the case then there are only smooth ramps (within a diminishing space) for each roller to become "jammed" so to speak, against the outer raceway drum when engaging. Both designs work the same though.

 

[retro]

How do I check the crank main bearing? Just wiggle it around for vertical and horizontal movement? Im kinda scared what I'll find because there is some rattly noise in that area when your just kinda just rolling at light throttle.

Yep, grab hold of the crankshaft stub and try to wiggle it around in every direction.

Look around under that side cover for any other loose stuff too.

 

[agdodge4x4]

I had the cover off today, but did not think to check the crank. It has two bearings, so, I have no clue how to replace those except for complete engine tear down.

There was NO material of any kind inside the case though. No shavings, no chunks, maybe a couple of pieces of whatever on the screen, but otherwise, everything inside was shiny and clean. Would I have any other symptoms of a bad crank bearing? Shouldn't it make a TON of noise? Like...it should be knocking, like a car motor, right?

 

[retro]

If a main bearing gets loose enough it will certainly cause some lowerend noise. But if there are no other loose bearings or heavily worn parts in the motor, you may not hear a single main bearing getting loose until its really shot. Every instance of a possible failing part can appear to be unique... universe seems to remind us often that we know nothing until we do...

EDIT:
I'm not saying you have a loose main bearing in your motor... this is just a discussion of the possible... in event someone else stumbles onto this thread someday.

 

[agdodge4x4]

The spinning noise at shutdown in neutral has ceased since I adjusted the clutch. To adjust my clutch, doing it as per the manual (feel resistance, back off 1/4 turn) yields a rubbing noise when you push teh clutch pedal up before clicking to shift. If I back off teh nut another 1/4 turn, its quiet. No idea what thats about. Seems to shift ok as long as you put pressure on the bar before letting off teh throttle to push it up. Clicks right in.