Rear cylinder valves.

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Waylander

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Is it possible to get at these without dropping the motor out of the bike?

And if not, how complicated is that?
I have the full on shop service manual which shows most of the steps but I'm wondering if I have to worry about all the electrics and shit, or if I can just pop the valve cover off while it's still in the frame hopefully.
 
not really sure what you are asking, if you want to adjust the valves it can be done while the engine is in the bike. I prefer to do it out of the bike but that's not at all required. Getting the covers off can be a challenge and you have to remove a few parts to get the clearance for them to slide out.

Sean
 
I take the exhaust off.Then remove the front motor mounts and drop the front down on a floor jack.Pivoting on the rear mounts.
 
not really sure what you are asking, if you want to adjust the valves it can be done while the engine is in the bike. I prefer to do it out of the bike but that's not at all required. Getting the covers off can be a challenge and you have to remove a few parts to get the clearance for them to slide out.

Sean
Not really adjusting the valves but me and my mates reckon the reason it's making that lousy tapping sound and has no power is cause one of the shims has busted and fallen out knocking things out of alignment.

To me the simplest way to do it would be with the motor in the bike.

I guess what I'm asking is, is it less work to drop the motor out or remove all the stuff around the rear cylinders. Which way has me unbolting as little as possible.
 
If it spit a shim out the cam is going to be shot. Not only that but the engine is likely to follow since there would now be a lot of material that is passing throught the oiling system and engine.

It may simple need an adjustment which you can do with the engine in the bike.

Sean
 
If it spit a shim out the cam is going to be shot. Not only that but the engine is likely to follow since there would now be a lot of material that is passing throught the oiling system and engine.

It may simple need an adjustment which you can do with the engine in the bike.

Sean
Great so I've got a really big expensive paperweight out in the garage.
Don't know what I'm doing enough to fix that kind of mess and don't have the money to get a shop to fix it.
 
Would a compression test tell if one of the shims was out? Or at least wouldn't one of the cylinders compression be wildly different if one of the valves isn't being held open as long as it should be?

Just thinking out loud....

Rusty
 
it would show at least a difference. What I would do is pull the valve covers and see if it has indeed shucked a shim. More then likely it hasn't but anything is possible.

If it has then check the damage. It will have wasted the cam more then likely. So, I would get a replacement cam and install it. Of course you would clean out the engine as best you can too and drain the oil completely. It may not hurt to remove the oil pan to get as much as possible out of the engine and clean up the residue everywhere. You can flush the engine out pretty well that way and try to give the engine a chance to live again.

If he cought it soon enough he may still be OK to install the replacement cam and still be fine.

Sean Morley
 
it would show at least a difference. What I would do is pull the valve covers and see if it has indeed shucked a shim. More then likely it hasn't but anything is possible.

If it has then check the damage. It will have wasted the cam more then likely. So, I would get a replacement cam and install it. Of course you would clean out the engine as best you can too and drain the oil completely. It may not hurt to remove the oil pan to get as much as possible out of the engine and clean up the residue everywhere. You can flush the engine out pretty well that way and try to give the engine a chance to live again.

If he cought it soon enough he may still be OK to install the replacement cam and still be fine.

Sean Morley
It kept dieing on me on the day, thought it was the bat getting low so was just push starting it till it wouldn't start anymore. After letting it sit for a bit and watching the rest of the drags I got it started but was making a small tapping sound.
Rode it for about 30 mins till the tapping got so bad I had to stop.
Nothing else was bad other than the tapping and loss of power.
No wrong sounds from anywhere else.
 
The key is what exactly is the "tapping" sound. Could it be more of a "knocking" sound? If you were at the drags and it started then I would venture to say you probably spun a bearing on one of your runs. I've done that more then one time myself. The loss in power, and the fact it won't turn over now means it probably seized the engine.

Drain the oil into a catch pan and look and see if there are any metal particals (looking for brass color). If so it's done. It's no consolation but I will have some 1300 engines in the shop soon that I will be converting to vmax specs. I think I will be getting a few regular engines too but of course anything can be built from scratch if that's what you decide too. OR - you can part out the bike and start over with another one.

Sean Morley
 
The key is what exactly is the "tapping" sound. Could it be more of a "knocking" sound? If you were at the drags and it started then I would venture to say you probably spun a bearing on one of your runs. I've done that more then one time myself. The loss in power, and the fact it won't turn over now means it probably seized the engine.

Drain the oil into a catch pan and look and see if there are any metal particals (looking for brass color). If so it's done. It's no consolation but I will have some 1300 engines in the shop soon that I will be converting to vmax specs. I think I will be getting a few regular engines too but of course anything can be built from scratch if that's what you decide too. OR - you can part out the bike and start over with another one.

Sean Morley

Mate if I could afford a new engine for this things I wouldn't have a problem. Trying to fix and sell it to get money up to buy a new bike.
 
You can part the bike out if you take the time. It will bring enough in parts that you can probably buy a new bike with the money raised.

Sean
 
LOL, yea right!

I don't really know how many 1300 cases I have. I know I am getting ready to assemble one for my chrome bike to get me throught the season until I finish up my 1500 (it may not take all season). The 1300 I am putting together should make a sold mid 140's I am hoping on RWHP and will be available when the 1500 is ready.

Sean Morley
 
I take the exhaust off.Then remove the front motor mounts and drop the front down on a floor jack.Pivoting on the rear mounts.

1. Does the entire exhaust have to come off?
2. Does this procedure make replacing front and rear gaskets easier or just the front?
3. Is it worth the extra effort?
 
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