New to me 85 V max Questions

[yellowandfast]

Bike has 45,000 miles on it
runs strong, NO noises whatsoever from engine

is there any way to tell if the update for 2nd gear has been done?

is there a certain vin number that would be the cut off for the revision, or did all 85 maxes have the issue?

and if not how hard is it to do so?

and what are the differences in the "n" vs the "nc"

any other things I should look at before I start the riding season?

I m crossing over from the Yamaha 2stroke world, I have a small collection of 70's bikes and have done several engines over the years.

any help would be great

Thanks
Jeremy

 

[DakRatFink]

I'm no expert on the model numbers, but I THINK nc = California model. As far as What VIN # have the 2nd gear fix, no clue, but someone on here might.
What part of WI are you from?

Oh yeah, and Welcome to the Forum!

 

[MaxMidnight]

Hello and welcome

If it has survived 45K then the gear has either been done or it ain't a problem.
Either way only start worrying if it becomes a problem.

To change it's an engine out, cases split to change but not a difficult job.

C as explained above is a Californian model which has some additional anti pollution kit attached. PAJ1 is a 100 v. 90 on the non C carbs.

Suggest that you start to ride and enjoy the bike....I'm sure that once you have a few miles under your tyres further questions will follow.

 

[yellowandfast]

Thanks for the replies.

I live in manitowoc, righjust south of green bay

anything else I should check or watch out for?

Thanks
Jeremy

 

[Rollie]

Thanks for the replies.

I live in manitowoc, righjust south of green bay

anything else I should check or watch out for?

Thanks
Jeremy

Rear view mirrors and the po po . :rofl_200:

Welcome to the addiction .

 

[RaWarrior]

Yamaha never really "fixed" second gear....really, it's a flaw of the 1-N-2 shift pattern....pretty much any bike of any vintage with that shift pattern is vulnerable to blowing out second if ridden/shifted harshly. I've heard of people with brand new M109's blowing second out from powershifting it from 1-2 all the time. My buddy with an R6 slips out of second on hard accel, again, from never bothering with the clutch. Bikes with a lot of power just tend to get this issue more often than weaker ones.
Always clutch your 1-2 shift and you'll be a lot better off.

If you have the california model, there will be a black canister stuffed behind the motor, some bullshit fuel tank vapor recovery thing. The jetting is also slightly different, as in leaner, and they have the anti-tamper plugs in the carbs.

 

[yellowandfast]

Nope no california model here.

I was unsure of what was the cause of the 2nd gear problem.
I will have to make sure to clutch it all the time I guess.

I have to put new throttle cables on it as they are slow to return and I found a crack in the "elbow" from the hand control.

Other than that I think I will be able to put some care free miles on it this summer.

Thanks again

Jeremy

 

[RaWarrior]

Couple things to check up on, to prevent issues down the road.

1. Check your voltage. The Vmax is notorious for having a lousy electrical/charging system. Put a voltmeter on your battery with the motor idling, and then at say 3000RPM. Ideally you want at least 13v at idle at 14.4 revved up, but as long as it picks up to 13.5 or so while at driving RPMs you should be OK. If your voltage is less than 13v revved up, I'd investigate the charging system since it's extremely marginal. In any case, I'd suggest cutting out the connector between the stator and R/R (3 black wires), and crimping them directly with blue connectors. Also, cut the connectors out from the black and red +/- wires from the R/R, and wire both directly to the battery. This will bypass the "crimp" in the factory harness that's a known "choke point".

2. Check/change the final drive oil. Lots of people completely forget about this. It takes a few ounces of standard gear oil....virtually anything will do. I used MerCruiser gearcase oil because I had some handy....and a marine gearcase is essentially the same thing.

3. Run the bike in a dark area and look for any arcing from the wires/boots to the heads. If you see any, replace the wires.

4. Check the steering bearings for looseness. Do a search here for the "bounce test", or see Sean's (one2dmax) youtube channel for a video about how to do it. This can help prevent wobble (high speed) or wander(low speed).

 

[yellowandfast]

Cool, thanks again

I will have to check the rear fluid this week and get it replaced.

One thing I did notice is that it has a little hiccup when coming up to a stop sign and reving to down shift, I was going to run some seafoam thru it.

any suggestions on that?

THanks

Jeremy

 

[RaWarrior]

You can try some sea-foam, can't really hurt anything.

Otherwise, you can try doing the "shotgun" and "peashooter" techniques. Click the VMF Links button at the top of the page, there's links to tutorials for both.

 

[dingy]

The Ventures have the same second gear problems in the 83 through mid 85 year bikes. I think the last serial # for the Venture was 1415, but this probably couldn't be tied to the VMax serial numbers

What has been determined to be the cause is the thrust washer at the end of the shaft that you see under the middle drive cover was too soft. When this washer wore, it allowed the shaft and related gears to shift enough to start engagement problems with the gear dogs. As this engagement issue continues the dogs wear more and the problem worsens.

1st picture has arrows pointing to the cause of the problem. This can't be fixed without splitting the case even though you can touch it.

The Ventures have a punch mark on the serial number plate on some of the bikes that have had the second gear issue fixed by a dealer. 2nd picture shows an example of this punch mark. I don't have a clue if the VMax's were done like this though.

Gary

 

[yellowandfast]

There is no punch mark there but there is other markings on the engine

up front on the left side (sitting on the bike) front motor mount there is "77" then 5666 under it?
and back by the engine stamping there is 97 and 94??

do those mean anything?

Checked the charging system and it makes 14 volts at just under 2000rpm so I should be good to go, also just changed the rear diff fluid, it was dark but NO metal in it what so ever, the magnetic drainplug wasnt even "fuzzy"



Jeremy

 

[dingy]

Those numbers were put on when the motor was manufactured. They indicate bearing journal sizes. These vary from block to block.

Gary

There is no punch mark there but there is other markings on the engine

up front on the left side (sitting on the bike) front motor mount there is "77" then 5666 under it?
and back by the engine stamping there is 97 and 94??

do those mean anything?

Checked the charging system and it makes 14 volts at just under 2000rpm so I should be good to go, also just changed the rear diff fluid, it was dark but NO metal in it what so ever, the magnetic drainplug wasnt even "fuzzy"



Jeremy

 

[one2dmax]

I disagree with Dingy's observations on the retaining clips. If you examine the newer transmissions you'll see there is a thrust washer added in later years under the secondary shaft outer bearing (on the opposite side of the one in your picture). There are a number of different sizes used.

I haven't been sending them in some of our past transmission builds though they have worked fine so far. We are however starting to send them so the customer can get the best possible transmission available.

Sean

 

[MaxMidnight]

Quote "standard gear oil....virtually anything will do"

Bare in mind that the final drive uses a hypoid gear and Yameringha specify an extreme pressure (EP), SAE80API - "GL4" oil.

I would be inclined to stick with that rather than the first thing you lay your hands on.

 

[dingy]

I would have to believe Sean's opinion that the VMax transmissions had a different problem.

Attached is a PDF that I think is from Yamaha detailing the problem with the Ventures. It is dated 8/16/85.

In it it says this improved thrust washer was used on all VMX12 bikes.

Gary