Safe or replace?

[Trashmasterrichie]

Hello, I had my chain break on my 2011 yz450F recently.

 

I noticed significant wear on the underside of the sqingarm by the front sprocket.  Not sure if the chain wore through over time or it just ripped though at one time.   

 

Take a look, do I need to replace the swing arm? Or do you think it is ok.  I do not do big jumps, just trail rids for the most part. 

[theBIGnaud]

Forward chain slider. Like 15.00 on amazon 

[SnowMule]

Chain slider's not even tehre at that point; you're seeing the raw aluminum of the swing arm.

 

I would try to find a machine shop that can weld that up and bore the swing arm out again, press in new bearings while they've got it. 

Most dealers probably won't go that far, they'd just quote you a new swing arm... but i'm betting if you shop/ask around, you could find a machine shop that could fix that for a hell of a lot cheaper than a new swing arm.

 

Other alternative, try used parts/scrapyards... see if there's a make/model that'd fit.  Cross-reference the part number on your bike vs. other models/years, get a year/model range that'll fit instead of just yours. 

Swing arm for my bike is used on pretty much all the 2- and 4-strokes from the late '90s to late '00s. 

[S.O.A.N.Z]

yep machine shop could build that up - had one done recently

[William1]

Yup, get it welded up AND replace that sprocket too. That is worn out!

[Doug.]

You can probably get that fixed by the right shop. A new swingarm is going to cost you around $150-$350 depending on what kind of bike you have. 

http://www.oemdirtbikeparts.com/swing-arm-swingarm-s/80.htm

Edited November 3, 2017 by dmcgill87

[FlyingDirtrider]

Yikes, looks like it was time for a new chain slider a LONG time ago! ?

I'd look at getting a new / used one unless you already know of a good machine shop nearby.
Otherwise the cost will likely be comparable.
I definitely would not leave it as is, big hole in there for water to enter as well as it being structurally compromised.

Also strongly recommend changing both sprockets! That front one is pretty worn.
Chains rarely snap on their own, they snap after they've been in service for way too long, or a new chain put on a fried sprocket.
Consult your owners manual for how much chain stretch is allowable.

[giron]

Hi, this is mine. We repair it by filling. Thats very good.

 

 

 

[The Inquisitor]

3 hours ago, giron said:

Hi, this is mine. We repair it by filling. Thats very good.

 

 

 

Damn dude that's a big hole and I'd like to see a pic of the repair but yes I that could be patched properly.

Otherwise to the OP, I agree that it could be fixed for a case of beer at a good shop and while your at it and besides a full swing arm rebuild, do a lower full linkage rebuild.

It's kinda hard to tell from this pic BUT this IMO is a long term issue and it looks like your chain has been adjusted way too tight but you need to find out why it wore through the slider there in the first place. Sorry if its obvious.

 

[Trashmasterrichie]

Chain was loose not tight.  I bought a new guard, sprockets and chain.  When I went to replace the guard I saw the damage...

[ka24s14am]

I'm glad I saw this. Mine has been making a noise from the chain. Now I have a darn good guess where I'm going to find where that noise is coming from.

I'll look when I get home from the hospital. Me and the wife are having our first baby!

[woods-rider]

eBay, can be had for like $50.

[Padilen]

Hey, I found some damage to my newly bought used DRZ.
I knew chain and sprockets needed replacement. But because of excessive old chain lube and dirt chain buffer looked good. I removed it to clean and found the only wear was approximately 1x1. Right into swing arm. I found a used swing arm in excellent shape, with a new chain buffer on it. I did not install the swing arm as my mental image was far worse than actual. Yours is in need of repair or replacement. I wanted to learn why this happened. I learned my DRZ had a 13 on it, this sprocket was the cause. So I'd suggest checking the CS size, and if it'
s a smaller CS, change to at least 1 additional tooth. Then rear tooth count to get your gearing back.

[Shhhh]

I'd replace it. 

[ERabe]

On 11/4/2017 at 3:46 AM, filterx said:

Everything looks REALLY dry around there, you're probably running an O-ring chain and that's cool, but a dry chain will eat up everything it touches really fast. I go through a can of chainlube every month on the 3 bikes we ride often. Just my 2 cents bro. ?

 

[The Inquisitor]

19 hours ago, ERabe said:

 

Just to be clear, that was not my quote under the picture but ya it does look dry and I lube the crap out of my chains before every ride and even sometimes afterwords if its really wet and the bike is going to sit for say a week.

[ERabe]

3 hours ago, filterx said:

Just to be clear, that was not my quote under the picture but ya it does look dry and I lube the crap out of my chains before every ride and even sometimes afterwords if its really wet and the bike is going to sit for say a week.

Oh hahaha! I just quoted your quote because you had already quoted the picture I was referring to, apologies FX! Maybe you would agree with me then that keeping that stuff wet with lube, I have never worn through a chain slider like that before in close on 20 years. I HAVE replaced them when I see them getting thin, but that's after probably 500 hours. A dry chain sliding against a rubber/plastic part at speed, makes heat, makes melted rubber/plastic in minutes. No denying that. ?

[MrN2OBelvedere]

Uggh replace it. That craps dangerous. Just cuz its a Yamaha doesn't mean zero maintenance. Since you waited too long to replace the chain n sprox now you have to replace the swing arm. Its ok, i guarantee you will find all your shock and linkage bearings all seized and rusted solid. Have fun!

[ERabe]

6 hours ago, MrN2OBelvedere said:

Uggh replace it. That craps dangerous. Just cuz its a Yamaha doesn't mean zero maintenance. Since you waited too long to replace the chain n sprox now you have to replace the swing arm. Its ok, i guarantee you will find all your shock and linkage bearings all seized and rusted solid. Have fun!

Damn dude, harsh much? The sprocket in his pic isn't even worn, and worn out chains and sprockets have no effect on the swingarm, or any bearings. The chain slider is worn through. While I do agree that it's definitely too dry around there, and proper lube-maintenance could have prevented it. Just#saying 

[The Inquisitor]

Regardless of the make of bike I agree that proper/regular maintenance and IMO is one of the main reasons I wash my bikes fairly frequently so can do a good visual inspection for broke/worn stuff, is KEY and most likely this would have prevented the swing arm getting this worn in the first place.

Now with that said, there have been things I put off doing (like my swing arm/lower linkage, fork oil, and nipples) and ya the swing arm/lower linkage was trashed and I'm now re greasing at least yearly, I'm now replacing my fork oil at least one a year and I'm not letting my nipples get this bad again cus I eventually had to replace the rim.

swing arm/lower linkage

nipples

Edited November 15, 2017 by filterx