[tylerjones]

20013 honda rancher 420
I recently changed my primary gear reduction back to stock. before I did this I had no clue what was reduced do to the previous owner not knowing, the primary or output gears, so first instinct was output, I tore down the rear case of the block where the output is and it was stock. I rebuilt it by the book. I test drove it, there was a currrrr noise (sounded like metal on metal) in the front case (keep in mind I tore the rear down first) so I ignored it thinking when I tear down the front for the primary gear I might find a solution. I didn't. I changed out the primary gears to stock with used from a guy local (traded) I rebuilt the front end by the book. except I did not notch the 34mm nuts. the noise is still there and when I cut the bike off there's something still spinning with the loud currr noise (sounds like a bearing when dry spinning.)
I'm looking for some input thanks guys. note it is a 2013 trx420fm 4x4

 

[SamUK]

The first questions folks are going to ask is... Has or did this ATV have a snorkel fitted and, has it been sunk or used in deep mud/water to your knowledge?

A curr, whirr or whine is a characteristic of a worn bearing, but could also be that of something catching, such as a clutch basket on a casing. Did you check your one way bearing while you were changing the GR over? Does the whine happen in any other situations such as acceleration, deceleration, acceleration under heavier loading, revving whilst stationary?

Ideally we need a little more information to try and pin point an issue.

Also, I can’t say for sure on a 420 (refer to the FSM) but on a 300 there is a washer between the primary gear and oil pump gear, if that washer is missing (which it may well be) then this stands a high chance of being your issue.
Some GR’s require a washer and some don’t, just depends how they are made, the OEM primary definitely requires the washer.
Check the FSM to be sure on your model

 

[Goober]

Does this model have a one-way bearing? I had that with a much older model; it didn’t hurt the operation that I know about but it was an annoying little growling noise on shutdown

 

[SamUK]

FM have a one way bearing, not sure about the ES/Auto models, I steer clear of those.

 

[tylerjones]

the bike had snorkels and radiator relocated, yes previous owner sunk it multiple times. I honestly did not check the one way bearing. I assumed it was ok. the bike did not make the noise until I did what I did. it started when I worked on rear case first.
the noise occurs when the bike cranks up. it makes the noise while accelerating and deceleration.
I do not recall seeing a washer.
before I rebuild the front case I gave everything a good spin. lol I guess my spinning is not fast enough to justify the noise before assembly. the bike runs great just the noise. I'm afraid it might mess something up

 

[SamUK]

There’s not a lot in the rear case that can cause noise, you’ve got the bearing on the through shaft and the flywheel. Did you remove the flywheel at all? Not a pull cord issue is it?

 

[retro]

the noise is still there and when I cut the bike off there's something still spinning with the loud currr noise (sounds like a bearing when dry spinning.)

One-way bearing is shot.

the bike had snorkels and radiator relocated, yes previous owner sunk it multiple times. I honestly did not check the one way bearing. I assumed it was ok.

Its shot. Making assumptions will put ya in the trick bag every time... :-(

There may be other issues as well... it was a mudder so expect the worse, but hope for the best!

 

[LBZ_Duramax]

the bike had snorkels and radiator relocated, yes previous owner sunk it multiple times. I honestly did not check the one way bearing. I assumed it was ok. the bike did not make the noise until I did what I did. it started when I worked on rear case first.
the noise occurs when the bike cranks up. it makes the noise while accelerating and deceleration.
I do not recall seeing a washer.
before I rebuild the front case I gave everything a good spin. lol I guess my spinning is not fast enough to justify the noise before assembly. the bike runs great just the noise. I'm afraid it might mess something up

Check good for that washer, It was with the primary gear when I gave it to you. If not I probably have an extra I can mail to you. I believe between the washer and one way bearing you will find your noise.

 

[tylerjones]

the washer isnt there. it might have got lost during transaction to home. could you pm me I can send you my adress and set up a payment

 

[tylerjones]

There’s not a lot in the rear case that can cause noise, you’ve got the bearing on the through shaft and the flywheel. Did you remove the flywheel at all? Not a pull cord issue is it?

I did not remove the flywheel, o pull cord on this bike, that is fro the response

 

[tylerjones]

ive searches for the one way bearing I can ot find a part number could someone give me a hand please.

 

[billy5221]

Go to Partzilla.com under your machine go to clutch and I believe its #26 clutch one way

 

[shadetree]

which one-way bearing are you after ?. there are two on your atv. one is on the flywheel, other is on the centrifugal clutch .

 

[tylerjones]

I honestly don't know which one the gentleman was refering to as, I seen the one someone mentioned in the clutch. is there any way to diagnose this with out tearing down first?

 

[c1v1c966554]

Idk what bearing is bad, but maybe a simple question could help?

Does the bike engine brake while going down a hill?

 

[retro]

If I remember right you said that there was a whirring noise in the motor immediately following shutdown? If so, that is an indication that the one-way sprag in the centrifugal clutch drum may be shot. There are three parts to it... all must be replaced at the same time.

 

[tylerjones]

If anyone would like to hear it please PM me for my phone number i have a breif video of the noise