Jump to content

  • Join Today, It's Simple and FREE!

    As a member, you can post in our forums, upload your photos and videos, use and contribute to our downloads, create your own member page, add your ATV events, and even start your own ATV club to host your own club forum and gallery.  Registration is fast and you can even login with social network accounts to sync your profiles and content.


2004 350 Bruin caliper mounting problem

Recommended Posts

Hello! I don't own any ATVs but I am into everything else mechanical. The reason for my post is a co-worker who has a bunch of ATVs but is not mechanically inclined or like to post on forums has a 2004 Yamaha 350 Bruin that hasn't ran in a several years because of a mechanically issue. I told him I'd help him get it running. The float valve and jets probably need to be cleaned in the carburetor which shouldn't be a big deal.

I have not seen it but here is the problem he describes.

The piece that the caliper bolts to broke at some point. I don't know if this is a simple caliper bracket like on a car or it's the control arm or what this piece is.

So he bought an OEM part off Ebay. Afterwards the upper caliper bolt holes don't line up. So for awhile he left just the bottom bolt holding the caliper in place but says eventually the caliper moves about and starts rubbing the inside of the wheel.

The way he talks the lower bolt holes line up but the other one is off by half and inch or so.

He wanted to see if we could enlarge the hole in the caliper or enlarge the hole in the bracket and use a larger diameter bolt and nut so the holes would line up but that sound dodgy and I don't think a person should have to modify an OEM part to make it fit.

I told him perhaps there was a design change mid-year or got sent the wrong part to begin with and he needs to find the correct part.

Does any of this sound familiar? 

Share this post

Link to post
Share on other sites

Here is a photo I captured from a YouTube video of a guy doing a brake job on his 350.

Apparently the piece is the larger disc with holes in it behind the brake rotor.




Share this post

Link to post
Share on other sites

Well we got the Bruin fixed. Took the carburetor off and gave it a good cleaning. This has to be the most complicated carburetor I've ever seen outside a Rochester Quadrajet! I did not have a good feeling but after cleaning the jets it no longer cuts out and backfires under full throttle. Cleaning gummed up carburetors on stuff sitting around with 5 years of evaporated fuel seems to be hit or miss.

Now onto the front end. Turns out the kingpin was the correct part, everything else was boogered up.

Turned out the rotor and the caliper mounting bracket were bent from where the kingpin had broke. That was why the bottom hole in the caliper bracket did not line up with the kingpin. Also the rotor had wore a groove into caliper, almost through one of the pad pins, halfway through the other and sheared off the peg and the bolt in the caliper mounting bracket.

So we got a used hub with rotor + lug nuts, caliper mounting bracket, new pads and a new pad pin ($9.00!). $72 in mostly used parts.

Yamaha's front brake caliper diagram does not show the bolt. I called the local Yamaha place and the guy seemed clueless at first but lead me to believe you had to buy the entire caliper to get it. OUCH!

So I had to improvise. I would NOT want to do this on car. I had cut 10 mm of this bolt off, install a bunch of nuts, grind the edges off so the caliper wouldn't wobble then to apply Locktite to the threads and adjust the bolt until the caliper was not in a bind. So far so good but I'd still like to fix it right.




The larger piece below is what I need to fix it right.



This link says this piece will not fit a Bruin 350 but it looks exactly like the part. But you know how Ebay's cross reference guide is. Yeah it may only fit a Raptor but it may also fit a Bruin but the seller does not indicate that it does.

Any idea if this bolt will fit a Bruin? 


Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Similar Forum Topics

    • By Pete Barber
      Pull in clutch lever shift into gear and nothing happens ... But When I pull in the clutch lever I hear a clicking sound ... never heard this before ...
    • By JacobSlabach
      Got a 04 Sportsman 500 that wasnt running- owner said it needed a stater and a new battery.  It ran rough (been sitting out in the weather for a while).  A friend and I started by adding a new battery and it would start barely with the choke and his hand over the air-filter.  I decided to install the new battery in the holder on the side.  we had it on the rack because the old on was still in the bike.  I tried to be nifty by turning the battery to put the terminals in an easier spot to get to, but forgot to reverse the cables too.  In a sentence, I reversed the positive and negative on the battery like a dummy.  When we discovered my mistake and corrected it, we turned on the bike, but the display did not light up and the key did not turn on the starter.  jumping the solenoid worked the starter, so we thought the solenoid just burned up when I reversed the pos and neg...  new solenoid and no difference.  what have I burned up?  Also, the shifter does not seem to do anything in the trans.  it slides back and forth like its stripped in the trans.  any help would be appreciated!!
      I think the biggest issue right now is the electrical.
    • By Wesley Floyd
      Hey guys, Thanks for looking at my post. I haven't had a lot of experience with problems like this before, so I'm a little bit at a loss. The Quad was really hard to shift, (the dirty carb leaking gas making it idle high didn't help either). The only Idea I have would be is that the torsion spring is worn out, and that there is a normal parameter for how much it should move when those two arms of the shift shaft assembly spread apart.  That's my thought. Maybe someone who has more knowledge then me can let me know if i'm on the right track 😀

    • By chem3233
      I have a 1998 yamaha grizzly 600 4x4 I have put back to life but as soon as I had all the bugs out it blew the special "L" plug out. What causes this? Is there something special I have to do to replace this?
    • By Alan Callison
      OK everybody,I need some help here please. My 4 wheeler has got a bad wheel bearing I discovered while starting a brake job. Its on the left side. I've never done one and I need some knowledge how to go about it. Am I to understand I need to pull the whole axle out to do it. I've done it once on a car about 30 years ago,lol. I keep looking around for a repair manual but they're hard to find without having to buy it. I looked here on this site but apparently Im too junior a member to be able to download one right now.Bummer!  One other question if I may.When I pulled the drum off the spindle a torrent of water poured out,the brake shoes were covered in mud along with everything else. I mean the drum had alot of water in it. The shoes were so locked up after I removed the springs I tried to rotate one of the shoes and it wasn't easy at all. I noticed whoever had the machine before myself had laid a bead of RTV around the back plate but apparently it didn't work. Isn't there some kind of gasket for this purpose. I saw it calls for a dust shield but surely this wont keep the brakes dry or will it. Thanks everybody.
  • Recently Browsing   0 members

    No registered users viewing this page.