Two Stroke Motocross

TSM Racing => YZ Project 2018 => Topic started by: rsmith on June 03, 2018, 04:13:09 PM

Title: Expected "surprises"
Post by: rsmith on June 03, 2018, 04:13:09 PM
I dug into the YZ project a bit more and tackled some of the expected issues, namely bad bearings.

I could feel the roughness in the steering head bearings in the handlebars so by extension I figured all the rest would be the same.

Steering head bearings:
(http://www.twostrokemotocross.com/images/2013YZ250SteeringBearings.jpg)

As expected the rear suspension bearings are in bad shape.
(http://www.twostrokemotocross.com/images/2013YZ250SwingArmBearings.jpg)

Dry and rusty:
(http://www.twostrokemotocross.com/images/2013YZ250RearBearings2.jpg)

The complete carnage:
(http://www.twostrokemotocross.com/images/2013YZ250AllBearings.jpg)

Not a single good bearing in the bunch.

I have seen a lot of debate around the need to take your brand new bike apart and apply grease to all the bearings. I think the answer to that is clear. If you live in the desert, never ride in the wet and only hand wash your bike maybe you can get away it.

For the rest of us, it is time well spent pulling it apart and putting some high quality waterproof grease in it when everything is new and shiny.
Title: Re: Expected "surprises"
Post by: eprovenzano on June 04, 2018, 05:57:45 AM
This is part of my winter maintenance schedule.  I blow apart everything and all moving parts get a slather of grease.  I've worked on enough bikes to know the trials and tribulations of removing a stuck / broken bearings.  I've made many a tool to help the eviction process... but sometimes the best tool is just a BFH (BIG F'IN HAMMER) and just pound away at it...
Title: Re: Expected "surprises"
Post by: _X_ on June 04, 2018, 02:57:10 PM
sadly this is the norm when buying a used bike.
Title: Re: Expected "surprises"
Post by: OldNSlow on June 05, 2018, 10:32:09 AM
Nicely done documenting this whole process....looking forward to more 'discoveries' (hopefully NOT this bad) with this YZ.

So many riders dont know about this stuff, and thats okay, no better time to learn than NOW.
Pay me now with a bit of preventative maintenance (low $) or pay me later when it fails (High $$$$$) and end your ride or race....
do the math!

Sadly, it is the norm of any and every used machine I have ever bought....
Been doing this dirt bike thing since the early 70s...and learned through the years (yes the hard way) the HUGE difference between
preventative maintenance
vs
reactive maintenance

Wife at first (well she still does)thought (knows) I was NUTS off my rocker when I bring a brand new bike home and I take it to the frame bearing and electric/controls wise.
Grease every bearing
Inspect and dielectric grease every electric connection
tighten the bolts and those I bolts and nuts I take off to do the tear down are thread lubed.
I keep ride and maintenance logs on all my bikes (amazing for resale to have that documentation) and I know how long its been since I did 'X' or Y or Z and how many hours on the oil, top end etc (on top of engine hours)

I dont mechanical DNF (my body does now LOL )

Used bikes? 
I AUTOMATICALLY assume the $$$ to replace high stress bearings etc when I get it home - cause my 40+ years of experience tell me the PO didnt maintain it (even if it looks tight) and she is gonna need 'RMATV' parts ordering love to get right.



OnS
Title: Re: Expected "surprises"
Post by: rsmith on June 05, 2018, 10:40:21 AM
OnS:

Ditto on everything you said.

We bought this specific bike because I absolutely knew it would be like this and figured it would be a great topic for TSM on what to do and what to expect from any used bike you buy.

Wait until you see the piston...