Is a Honda really built better than the rest?

This RMZ450 cam has less than 20 hours on it :

http://www.ericgorr.com/images/drn/rmz450_exh_lobe_1.jpg

http://www.ericgorr.com/images/drn/rmz450_exh_lobe_1b.jpg

http://www.ericgorr.com/images/drn/rmz450_exh_lobe_2a.jpg

http://www.ericgorr.com/images/drn/rmz450_exh_lobe_closing%20side.jpg

The RMZ's intake cam looked almost exactly the same, but oddly enough the intake valves were in fairly decent shape. The rings and piston were completely shagged. It smoked like a two-stroke when it came in.

This CRF 450 cam has 2 full seasons :

http://www.ericgorr.com/images/drn/HondaCRF450_03_2_seasons%20on%20cam.jpg

Forensic work on engines sure is interesting. :applause:

All pictures are of the closing ramp side of the cams.

Same rider/maintenance schedule?

honda=win

i've had a 1982 XR200 for about as long as i can remember, and my dad had it before i did, and it still runs. i don't think i'll buy anything but honda.

Looks like the top end was starved of oil.

Same rider/maintenance schedule?

No, different riders and different skill levels. The RMZ450 is ridden by a SUPER FAST Vet rider. The CRF450 was ridden by a normal vet rider.

It's far from scientific, I just thought the comparison was interesting.

I think the fast guys are going to find the RMZ450s to be expensive to own.

Same rider/maintenance schedule?

It wouldnt really matter. Given the amount of use on the CRF cam and the amount of wear/nicks and crap on the RMZ cam I come to this conclusion:

Either

A. The Honda cam is considerably better material and was maintained with decent valve springs

Or

B. The RMZ comes with valve springs made of some kind of lead alloy that sacked almost immediately and allowed them to float and bounce like hell, or the cam is made of lead or both...or the rider lived on the rev limiter...

Or the RMZ had a bad timing chain that was flopping around, which I doubt simply because of the guy posting the pics. Regardless. the cam out of the RMZ looks like hell considering its only got 20 hours on it. Those big nicks look like valve to piston contact to me...or thats the shittiest cam blank I've ever seen...

Looks like the top end was starved of oil.

There are no indications of that anywhere in the engine. I think it's more a matter of Suzuki using over the top cam dynamics in this engine just like they did in the RMZ250. You can feel the ridges (dark spots) in the lobe face where the bucket was crashing down after jumping off the lobe.

This thing looks like it's a harmonics nightmare when it's ridden hard.

What oils are they running????

honda=win

i've had a 1982 XR200 for about as long as i can remember, and my dad had it before i did, and it still runs. i don't think i'll buy anything but honda.

This is a long story, why I bought my 450X, the XR200, and is IMHO, worth reading.

2 years ago I bought a 1986 XR200 from a farmer in North Dakota where I lived. The thing started right up, ran really well, but it had some mechanical clink-clink-clink noise that increased as engine RPM increased. I had a lot of fun on thsi bike, in the trails of the riding areas in ND. Putting around, gassing it in straightaways, it didn't have a lot of power, but it NEVER let me down, not once. Granted, I didn't have it very long (3/4 year or so)....

Then came that faitful day! I ride on a track near a riverbed, the Missouri river to be exact. Well, the water was a little low, and there were "Islands" about 40' from the sand bars. I saw guys on quads riding on the islands, so I figured the water would definately be crossable, but I was still a little leery. So I waited for some brave soul to cross from the sandbar to the island, and when they did, I would follow them.

And I did. To one of the smaller islands, not the big one where most of the people were. I had my fun on the little island, and wanted to traverse to the larger one, which was about 8' of water away (Between the islands). I watched the guy traverse the water, it wasn't more than 6" deep, so I followed him, but approx 6" off axis from his tire tracks. Well, that 6" turned into a 10' deep water pit. The next thing I know I hear the engine go under the water (As you'd expect it, a muffled idling sound that got quiter and quieter, but real fast), and I am SWIMMING over to the next island.

I stand there, in disbelief, looking into the dark water, unable to see even a hint of my motorcycle. My wallet and cell phone were on the little pouch on the rear fender, so I HAD to get the damn bike out of there. I found a nice kid on a big Arctic Cat quad WITH A WINCH. I threw his line in the water, "Fishing" for a motorcycle, where I THOUGHT I saw a red tint, but could not be sure. It was also starting to rain, and I was shivering from the cold...

I finally "Caught" the spoke of the front wheel, and we reeled 'er in.... A big fish indeed! The kid was nice enough to help push the bike (Oh, it was in gear for about 100 feet, we wondered why it was so damn hard to push) back to my truck, where I gave him the remainder of my gas (If I had cash on me I'd have given it to him!). I took the bike home, drained everything, and began taking the engine apart.

I have pics somewhere of the engine carnage I found... It turns out, that the clink-clink-clink noise was the CAMSHAFT CHAIN slapping against the CYLINDER, because it was loose. As it slapped the cylinder, it ate away the cylinder wall, producing massive amounts of shavings that were spread throughout the engine and trans. These shavings DESTROYED the oil pump, and the bike was getting NO OIL to the head for God knows how long.

The result was a camshaft that had worn down to 3/4 of an " or less at the bushing, and looked like it was "Polished" with a plasma torch. The bushing looked like it had bunches of metal strips welded erratically throughout the inside.. the lobes looked OK, but not great! The main bearings for the crankshaft were shot, there was enough wobble in them to almost pop the races clean out. The camshaft chain sprocket on the crank was worn so badly I was lucky it didn't repeatedly skip teeth.

How did the bike run? It ran great. A little vibration, but it started 1-2 kick, got great mileage, and revved when I needed it to. The transmission was in great shape, too. I bought 2 different lower ends and 1 upper end off of Ebay, they ALL had the same problem. I took the best parts from each engine (The majority of which were ALL WAYYYYY out of "replace" spec), threw it together, and rode it around like I did the other one, This one smoked a tad, but was as reliable as the first. There are a hand full of engines in the world that can suffer from that degree of rapid and excessive wear and still start easily, and produce useable power.

Hence my Honda 450X.

Great story. Must have sucked sinking your bike. How did everyone else get across?

Great story. Must have sucked sinking your bike. How did everyone else get across?

It was amazing sinking it, I learned a lot, better on a beater than on my Cannondale or my 450X! The water wasn't deap a lot fo places, but it ALL was dark, and overcast, so you could NOT tell the depth. Plus the river was moving, so there were ripples and whatnot everywhere. Everyone got across by crossing the shallow areas. If I would have followed the guy in front of me perfectly, I would have made it fine. What a difference a few inches makes!

That's why I always test the water with a stick or get a friend to go ahead of me. :applause:

Back to the subject, yes Honda's are built better than the rest. Just look at some of the CRF's and the craftsmanship that goes into them.

While looking at the cams and there is a visual distinction, remember to take into account the mechanics of the motors. Each motor is different with different thresholds. Is it fair to compare the Honda's single cam design to the dual cam of the RMZ? Is the load bearing on the cam or on the buckets? I am asking, you are more of an expert in this arena then I.

To answer your question, I feel yes, Suzuki bikes are more disposable then a Honda. The craftsmanship is better.

The cam cap/bearing in the head has a full circle groove , so the area in the center of the bearing that looks galled is just the space where the groove sits.

At first glance it's easy to think this was an oil related issue , but when you get the parts in your hands is easy to tell it's not likely to be the case. The area of greater pressure on the cam (and the place where the oil has to work the hardest) is the nose of the cam . There is no real indication of excessive wear on the nose (I'll take some new pics tonight). If the oil was the root cause the nose would show signs of it. My guess is the bucket is lofted over the nose at high rpm rather than staying in contact with it. The ridges on the closing ramp aren't galled like you would see in a normal oil breakdown situation, they feel very consistent and evenly spaced, like you see in harmonic patterns. A high zinc oil might have helped, but there are no oils in existence that can cure oddball cam dynamics.

This is a rider who revs the bike hard, and it looks like the valvetrain just isn't up to it, even when new. For the average rider it seems unlikely this is going to prove to be an issue. I guess time will tell.

good info.thanks rich.

Here are mine after 70 hours. I believe that what looks like scoring is only discoloration. I feel no roughness or gouges.

B-rider here.

http://www.locastros.com/campic1.htm

http://www.locastros.com/campic2.htm

http://www.locastros.com/campic3.htm

http://www.locastros.com/campic4.htm

http://www.locastros.com/campic5.htm

yours looks good, its possible that its a quality controll issue with the valve springs , witch is what I think could explain why some hondas have valve problems and some dont , I'm with Rich though, it looks like valve toss in his pics, weather its too radical of a profile or not enough spring pressure is the question

my 03crf cam looks better than that crf's----just kidding -it looks the same :applause::bonk::cry::cry::cry::p:lol::bonk::bonk::bonk::bonk::bonk::bonk::bonk::bonk:

I toyed with the idea of going orange for 06....then I thought about all the reliable hondas I have owned from an xr75 to an xr500 then a xr600 and a crf450. Take care of the valve issue on the crf and they wont let you down. Hondas are the best. I sure like that 250sxf but I am afraid it is an expensive timebomb.

I went too close to a stump on my CT70 when I was a kid and caught the peg on the stump as I went by in 3rd. The pegs are mounted to the engine cases and the whole assembly ripped out. Drained the oil completely. Being a kid, and no doubt dazed from the crash that left blue paint on the hardpack where my home-painted helmet met the ground, I rode that sucker home. Or at least some of the way home. The noise that that thing made when it finally stopped was incredible. That cam was deeply grooved, pitted, and burnt. So was the piston and cylinder wall. Good times! :thumbsup::thumbsup:

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