• A few people have been scammed on the site, Only use paypal to pay for items for sale by other members. If they will not use paypal, its likely a scam NEVER SEND E-TRANSFERS OF ANY KIND.

Engine FAILURE only 34 miles on bike

Too bad for him. Why in the world would he think he'd get a 'new' bike? For one thing, he already has one. For another, only the engine broke, and the warranty says they'll fix what breaks. I don't understand that kind of nonsense.
 
What's a valve rocker hinge rod? The 500 is shim under bucket and the valves are actuated directly off the cam. There are no valve rockers (rocker arms) in that motor. Must have been something else.
 
Easier for Honda to replace with new bike although business practice is to repair. He should get a spare bike to ride for free during repair period but conditions vary from locations to locations.
 
If they can prove the retaining bolt/screw was never there in the first place, then easy fix. Slide the shaft in and bolt it down. If the screw was there and is now MIA, then I'd be a little more worried. I'd want the side cover on the cam-chain side removed and everything inspected until that bolt is found.
 
Bad deal for the owner, and I would at least be talking to the Rep to see about a motor replacement. Hopefully Honda's QA is tracking down why there was an early life failure. That could have been a disaster if he/she had gotten injured, or worse due to the failure.
 
Big Thump said:
Bad deal for the owner, and I would at least be talking to the Rep to see about a motor replacement. Hopefully Honda's QA is tracking down why there was an early life failure. That could have been a disaster if he/she had gotten injured, or worse due to the failure.
Click to expand...

The bike is assembled in Thailand. Not sure if that means the engine didn't come from Japan or not.

Honda is really making great strides in cutting costs with its new bikes. I suppose they have too as the Chinese knockoffs keep getting better. Part of the cost savings comes from global sourcing. There are bound to be problems when any production is taken out of a well established controlled process and sent out to the lowest bidder. If they can minimize the damage to reputation they win big.
 
buckshot said:
Not according to this diagram.

Honda Parts for Motorcycle, Scooter, ATV and Utility Vehicles Dillon Brothers MotorSports Omaha, NE 800-964-1882

It's likely designed that way to ease valve adjustment. Rather than removing the camshafts and having to re-time the engine, just pull the rocker shaft and rockers.
Click to expand...
You are right, I was wrong to assume shim under bucket was like all the other designs I have seen or adjusted. None of those had rocker arms like this motor.
 
If I didn't look it up first I'd also wonder why there would be rockers in a DOHC shim under bucked head also. But, having done a few valve adjustments on typical DOHC engines I can definitely understand this design from a maintenance stand point.
 
^^^ It's not really for ease of maintenance as direct actuating shim over bucket is probably the easiest to adjust valves second to screw nuts if you have the spring compression tool. Conventional direct actuation of valves puts a lot of bending force on the valves. This necessitates bigger valve stems and guides to cope with the force. Bigger valves mean bigger springs. This means bigger impact forces for the valves and quicker valve recession.

Honda has done a lot of really good engineering for long term reliability and this ones a smart one. Heavily sprung valves just recede quicker. These rocker actuated valves are lighter, require less spring force to close and are less likely to leak long term due to worn valve guide bushings. The disadvantage is the reciprocating mass limits the rev ceiling more.

This is actually a lesson learned long ago with the lowly pushrod engine. They tended to not wear their valve guide bushings as much as DOHC engines. I guess this design is like a compromise taking the best of both worlds with a rocker setup like a pushrod engine but the lighter reciprocating mass OHC and shim and bucket designs.
 
Mr_Krabs said:
^^^ It's not really for ease of maintenance as direct actuating shim over bucket is probably the easiest to adjust valves second to screw nuts if you have the spring compression tool. Conventional direct actuation of valves puts a lot of bending force on the valves. This necessitates bigger valve stems and guides to cope with the force. Bigger valves mean bigger springs. This means bigger impact forces for the valves and quicker valve recession.

Honda has done a lot of really good engineering for long term reliability and this ones a smart one. Heavily sprung valves just recede quicker. These rocker actuated valves are lighter, require less spring force to close and are less likely to leak long term due to worn valve guide bushings. The disadvantage is the reciprocating mass limits the rev ceiling more.

This is actually a lesson learned long ago with the lowly pushrod engine. They tended to not wear their valve guide bushings as much as DOHC engines. I guess this design is like a compromise taking the best of both worlds with a rocker setup like a pushrod engine but the lighter reciprocating mass OHC and shim and bucket designs.
Click to expand...
Maybe so, but there are plenty of DOHC Honda motorcycles with direct shim under bucket valve trains with 100, 200, 300, and over 400,000 miles on them and the engines have never been opened up. I can't agree they are easy to adjust because you have to pull the camshafts to change shims but since the valve clearances actually change very little this adjustment is not often required. My ST did not require a shim change until 86,000 miles and then it was only one of 16. Since I had to do that one I moved 4 others back to middle of tolerance. The last check at 116,xxx miles the clearances remained stable from 86,xxx then a check at 106,xxx miles.
 
This is something that happens, but every dealership has the ability to rebuild any engine from the ground up. Time consuming but always doable. That's why the techs at the dealerships are so well trained, and yes it cost more to use them. This is a warranty job, so the companies know in advance from the warranty time books exactly what it will cost them. These time books are done in the perfect situation, which never happens in real life. So, dealer has to file for extra time. These books are used only in warranty situations, so never think that is the time any dealership will charge you for a job, in real life even the manufactures know they will pay more than listed in these books. The dealership gets nothing for comebacks, so the techs know to do it right the first time, and it usually is!7.jpg

SmileyMechanic.jpg

00.jpg
 
Last edited:
I saw a cut away CB500 engine it has a rod that the rockers ride on they are calling it a hinge rod i guess, looks like two rockers that are connected together actuate the intake and the exhaust are the same, looks to me like the are attached together and are Not separate, I could wrong and probably am.

But at any rate the rod came out through the valve cover I would think.
 
This guy did not want a engine that his dealer screwed with he wanted it to be as it was when brand new from the factory

I dont Blame him, I would have been Pi$$ed off.

Once that happens, quality of the entire bike becomes questionable, was the Tech/engine builder new, having a bad day/, did he miss something else, that will plague this bike.

I have seen it happen with Toyotas, in my years as a Tech for them
 
Last edited by a moderator:
The CB500 head design from what they were saying, you do Not pull the cams out.

You pull the rod out that came loose and failed, as this has the rocker arms attached to it.

Then the shims are right underneath

But you have to pull the Gas tank

Looks like Valve adjustment is done from upper rear of head, that is why the tank has to come out
 
Last edited by a moderator:
So, having had an engine that was "as it was from Japan" that exploded at 35 miles, one is worried that the local mechanic is going to do a WORSE job? That's non-sensical.
 
You would think with a brand new model, Honda would be wanting the best PR possible. So having this event plastered all over some forums is not what they would want. They would be better off replacing the bike and conducting a through investigation on this bike to see what failed.
 
You must log in or register to reply here.

Similar threads

admin
Guy Martin Guns for 200mph Record on Crighton 700W Rotary Bike
Replies
0
Views
570
admin
admin
admin
The 2023 Honda Motorcycle Lineup + Our Take on Each Model
Replies
2
Views
2K
Gixus
G
admin
2024 Royal Enfield Himalayan 450 Ride Review
Replies
0
Views
2K
admin
admin
admin
FOBO Bike 2 Smart Tire Pressure Monitoring System
Replies
0
Views
282
admin
admin
admin
2023 Moto Guzzi V100 Mandello S Ride & Review
Replies
1
Views
931
Lee_0123
Lee_0123
Back
Top