Wanna learn some things about restoration of a Vmax?

[Beau-Kat]

If you have some time, this is a restoration project with lots of photos. This guy went to extremes.

The cool part is that even he, being meticulous as he was, had a few problems like a lot of us have when trying to do things ourselves from time to time.

 

http://www.bikersassociationofnorthdevon.co.uk/projects/Vmax-renovation.htm

 

Rusty

[Blackmax88]

Hats off to that guy. Having done three Vmax rebuilds myself and ownd Vmaxes for 25 years he's covered the job warts an'all including his own mistakes. The pics are a great help to anyone wanting to rebuild a Max or a GenI Venture. Without "nitpicking" I'd draw attention to the infamous "Orange O ring" problem in the oil pressure gallery. Stated that this feeds the top end of the engine....it does supply oil to the camshafts but it mainly supplies oil to the crank and all main and big end bearings. This O ring displacement is common in all Yamaha V4 engines until Yamaha 'quietly' changed the design of the pressure elbow and O ring (without telling anyone) around 1998 so any V4 made before that date will have this problem. It just doesn't show up on Ventures because the engine is less stressed than the Vmax engine. An engine with a blown O ring will have zero zero oil pressure at hot idle and around half normal pressure above idle. If you ride in the high temperature / high rev zone with a blown O ring you are courting crankshaft disaster. Fortunately for Ventures, they don't get into this zone. The Vmax does.

FWIW.

[Beau-Kat]

Good info. Thanks.

 

I've only had one Vmax. My Vmax is a '98 that I've owned and maintained since Dec. of '99. Bought it with only 342 miles on it.

 

I've ridden all over the eastern US, but have always owned and ridden several bikes at the time. So the Vmax only has 25k miles on it now.

 

I've read a lot about the O ring issue before, but haven't been in the pan to check. So, I wonder if it might have the updated design? Guess I'll have to take a look.

 

I was looking back at the guy's "down to the last nut and bolt" rebuild. But I didn't see where he replaced the brake or clutch lines. I would have thought that he would have done the stainless steel line swap. Looks like he just cleaned up the ends.

[cowpuc]

Also didnt notice anything about upgrading for the 2nd gear issue, never owned one but heard they had the similar shim wear problem as our early 1st Gens.

Guy did a REALLY nice job and highly enjoyed the read! Thanks Beau for posting the link!

[Blackmax88]

"So, I wonder if it might have the updated design? Guess I'll have to take a look"

 

Not difficult if you have the time but before you do you may want to think about fitting an oil pressure gauge first. Mechanical or electronic it's not difficult, I prefer to make up the fitting rather than buy an expensive kit and have set up gauges on all my 'Maxes since 4 out of the 5 engines I've worked on had blown O rings, all identical faults.

If you go the gauge route you may not have to drop the pan and even if you do take a look, the gauge is a good addition.

On the problem itself, the O ring is not the problem....the design of the elbow, the oil pan support and the port which the elbow fits into ( 4 poorly designed details) all contribute to the problem. This combined with an oil pump pressure relief setting way above what's necessary all contribute to the O ring blow out. If Yam had redesigned one of these defects it may have solved the problem. There are several ways to "fix" the problem, the bracket shown in the article is cheap and it works but not what I do.

Agreed about the braided lines. There are many more upgrades which the Vmax benefits from.

FWIW

[Blackmax88]

Also didn't notice anything about upgrading for the 2nd gear issue, never owned one but heard they had the similar shim wear problem as our early 1st Gens

 

They did and the second gear problem was amplified by the fact that the Vmax applied nearly double the Venture's HP thru the transmission. The 'Max and the Gen I Venture share the same basic engine but even after the second gear problem was fixed by Yamaha, the Vmax could still slip second gear, often, due to riders "race changing" from 1st to 2nd.Once the dogs start to disengage, they only get worse. Usual fix is to get the gear's dogs undercut.