Jump to content
Sign in to follow this  

connecting rod is OUR culprit

Recommended Posts

Well I am glad you find it amusing, that's nice

I see you have a Yamaha as your signature pic, I assume you are a Yamaha guy... that probably has something to do with your feelings on the topic!! I suppose if I did not own an RMZ450 I could stop by this forum for a chuckle now and then also

Hey Whip, I was actually saying that I thought what you said about your '06 in the back of someone elses truck is the day you dream about. Not making fun of you or anyone else........ Yes I have a Yamaha, and No I don't say anyone is dumb for buying a suzuki. Its not like they knew there would be a problem with the bottom end. I didn't stop by this forum for a chuckle either! I started this thread to try to help anyone that might have a question as to what might be going on with their RMZ because I did the work on my friend's '05 RMZ 450! What bike I bought has no implication that I am smarter than anyone else, I took a chance with my bike because I heard nothing but good things about Yamaha's engines........ I never owned a Yamaha before my '05 WR450, only Hondas and I didn't like what I saw as common with their valve problems with the 250s. Please don't think I'm some dumba$$ kid in here spoutin my mouth off like I know that everything I do is right and everyone else is wrong..........

peace

Share this post


Link to post
Share on other sites

Gotcha...

no problem.

I have had many Yamaha 4-strokes. You will never hear so much as a peep from that thing....they are bulletproof, period. Enjoy!

Share this post


Link to post
Share on other sites
The noise from these already loud as heck engines increases slowly for a bit and then increases fast at the point just before seizure.

That describes exactly what I noticed. Mine was still running strong (with the loud clanking) when I stopped riding it. Still awaiting the phone call from the mechanic as to what other internal parts are damaged, but at least it didn't blow or seize.

I think this is the rebuild kit he was talking about using:

http://www.pro-x.com/images/nw_connrod.jpg

"PROX Connecting Rod Kits are made out of the toughest alloys available today. O.E. specifications and tolerances are meticulously maintained, a guarantee for easy installation and trouble free performance. PROX Connecting rod kit consists of connecting rod, small end bearing, big end bearing,big end pin and thrustwashers."

Share this post


Link to post
Share on other sites

Got the news, the Connecting Rod bearing breakage took out the cylinder ($500). They suggested also going with an Athena piston as it has better scuff resistance. The Athena piston and the ProX rod kit are $292. Add in $250 of other OEM items (bearings/seals/etc for the rebuild) and $400 labor, I'm looking at $1500 with tax.

The bummer is that a top end (piston, rings, valve seals, timing chain, springs, gaskets, etc) was $600 with labor. Let's say you need to do that every 50 hours. From what I've read here, the Connecting Rod bearing is only good for 60+ hours. So that means you should do top end and connecting rod bearing every 50 hours. Take the top end $600, add another $250-$300 labor for removing engine and complete tear down & crank unpress/repress, + $50 lower con rod bearing & tax and this all adds up to $1000 of maintenance every 50 hours. If I ride MX practice for 2 hours a weekend, then every 6 months I'll have to spend $1000, or almost double than a top end just because of a poor quality bearing and/or bad oil supply to the bearing design. Hopefully the ProX bearing is better materials so maybe I can go 100 hours for every crank/rod bearing rebuild.

Good thing I still have my 2004 RM250 in the garage.

Share this post


Link to post
Share on other sites

well i have owned an 05 06 and now an 07 and i can officially say it will be the last time i have a RMZ until they fix their problem. maybe its just me but every one i have had has ruint the motor by the crank bearing going out. i race GNCCs and other offroad series so i know the demand on the bike is high with all the mud and different conditions but i change the oil after every race and my dad is always tearing it seems so we do a lot of preventitive maintenece. the latest motor damage my dealer said is going to cost somewhere around $5500 to fix. i have had the bike around 3 months and if it wasnt for the suzuki bucks i wouldnt have bought another one to begin with. Dont get me wrong the bike handles great runs awesome for the woods and i have never had a problem with the bike starting hot or cold or with stalling. it just seems like when it goes it all goes. the t tube that runs to the right side radiator has melter twice losing all the coolant the first time resulting in a blown head gasket and a warped head and the second time the motor looks like it has been through a fire. if any one has had any thing similar happen a would like to know

ms859

Share this post


Link to post
Share on other sites

Your dealer apparently has a very bad crack smoking habit, even at rediculous retail prices, you should be able to build at least two complete RMZ450 motors from scratch for $5500

I agree with you though these things have some fundamental design flaw that has apparently not been addressed in any way. I do not buy the argument that there was just a run of bad parts and it is all set now. There is something about the fundamental design of the crankshaft of this bike that apparently places great stress on the road and crank pin. Part of it is the 4 speed tranny: more lugging in a high gear equals more stress on the rod.

I find myself lugging the thing in third around tight corners and two seconds later I am at high RPM's in the top of fourth. That is hard on a motor.That's a fact. But not a good escuse because Yamaha and kawi 4 speeds dont eat rods and rod bearings

There is something about this motor, I am 100 percent certain that if you hired an independant technical firm to do an analysis of this designh, they would find that there is something screwy about the crankshaft or its placement within the cases

Share this post


Link to post
Share on other sites

ya i agree, there is defintly some sort of design flaw in this motor. about 3years ago my first four stroke was a YZ250F. it was an 03 and i was just getting into racing and i kept that bike for the whole year and we changed the oil in it once and i raced probably thirty races and i never heard as much as a peep out of it and yes i race suzukis but i am a very strong believer iin yamahas durability and i think i will probably go back to one even though yamaha doesnt pay as much it would pay for its self in not having to rebuild it after three months. and yes i told my dealer there was no way i was paying $5500 for a new motor when i could buy a brand new bike for that.

Share this post


Link to post
Share on other sites

I wonder what is different about the Quad crank. Been looking around and they don't seem to have problems like these. The tranni on the other hand....

Share this post


Link to post
Share on other sites

Lower Rod problems are not new to Suzuki's. Guess I was an idiot for thinking it wouldn't happen to me. I was lucky and caought mine early. I got out out for just under $600. Thanks to great work from a great KTM shop. KRW in Phillipsburg, Ohio.

Looks like I'll be sandbagging the 250c class this year to try and recover some of my cost.

Share this post


Link to post
Share on other sites
ya i agree, there is defintly some sort of design flaw in this motor. about 3years ago my first four stroke was a YZ250F. it was an 03 and i was just getting into racing and i kept that bike for the whole year and we changed the oil in it once and i raced probably thirty races and i never heard as much as a peep out of it and yes i race suzukis but i am a very strong believer iin yamahas durability and i think i will probably go back to one even though yamaha doesnt pay as much it would pay for its self in not having to rebuild it after three months. and yes i told my dealer there was no way i was paying $5500 for a new motor when i could buy a brand new bike for that.

You raced this bike all year and changed the oil once and it ran fine? Now, first of all that is a horrible maintainence scheduel but it does not surprise me at all that a Yamaha could endure that type of abuse.

I know a guy who bought a brand new YZ450 a few yrs ago. Rode it once and did the first oil change, then forgot to tighten the drain plug. His oil drain plug worked its way loose and fell out midway through his second ride and he did not know it, he ran it 100% dry until it locked up. brand new bike

The Yamaha dealer took the top end apart and the only damage they could find was a scored cam journal. They smoothed the cam journal with a 3M pad and reassembled the bike AND IT RAN AWESOME FOR YEARS...as far as I know it is still going strong!!! I am not talking ran OK and burned oil or ran OK but was low on horsepower, I rode it a year and a half after this happened and compared to the new YZ450 that I was riding, his bike was every bit as fast, burned no oil and did not make any odd noises.

try that with an RMZ450, you cannot even keep the suzuki together if it is well maintained...the yamaha you can run with no oil and it still kicks ass

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

Reply with:

Sign in to follow this  

×