Rejetting the VF500F

I think you might have it backwards. I discussed the different sized mains in post #12.

I adjusted the valves. Most were loose about 2-3 thousandths. Cams look great. No mushrooming on the screws. That's really good news and I'll get a chance to post results on Friday. It runs pretty well but if I turn the idle to 1500 the revs hang when the throttle is blipped. Drop the idle to 1200 and it doesn't hang. Interesting. I may adjust the mixture screws another 1/4 turn out and see what happens. I also have to do a carb sync Thursday after work.

One note about the new boots (old ones were pretty crappy, BTW, with three having cracks) - the new boots are thinner than the old ones. ID is the same and the OD is smaller. This means that I had to tighten the clamps all the way to get them tight. Anything less and I could rotate them. I wonder if Honda did this intentionally to keep folks from tightening them too much. Just another thought to ponder..... The carbs went on wayyyy easier with the newer and thinner boots though. That was a blessing.

 

Good deal on the cams and the tappet screws. Glad to hear that these are in good shape.

Regarding the main jets - Honda had #102F/#105R mains in the '84 model. They then went to #90F/#90R in the '85 and '86.

 

Thanks Tink, got a good laugh out of this.

I wasn't trying to call anyone out here, rather I wasn't sure if we had a 'Who's on first, What's on second' conversation going on.

 

Actually, it didn't help this dialogue. It confirmed that this is a messed up topic. Note that the 84 has a larger rear than front and that the 86 version in parenthasis has a larger front than rear....oh, the confusion...

 

On a side note - I guess I was leaving out our California brethren here - the parenthesis refers to California models only.

 

So, you are saying people in Cali are backwards??? Just trying to clarify...

It really doesn't make sense. It's like the engineers changed their minds about up-draft/down-draft jetting requirements between 84 and 86.

 

No way! I'm a fan of Cali even though I'm a East Coaster...of course Canada, well that is another story...

I think it may have something to do with the California models having extra emissions add ons. The 'regular' '86 is #90F/#90R.

 

What you say about Canada? :canada:

 

A land of milk and honey!

 

More like Beer and Maple Syrup. :tongue:

 

...and Robertson screwdrivers and basketball (it's true) and hockey and Pam Anderson and Rush and the 09 White and Black VFR (sweet, wish I had the coin)...

Back to topic, I guess it is feasible that the emissions systems might require this mod, but these systems were in place for all three model years. Still doesn't make sense. My experience looking at my plugs is that they are all pretty darn even burning with the same jets front and back.

 

It is a bit of a head scratcher for sure. Some additional light reading:







Back on topic, Neil Young!

 

...and Glass Tiger, Celine Dion, Bryan Adams, Howie Mandel...

I'll give you William Shatner though, love that guy =P

 

Lol - take that bad with the good I guess. I can't believe that I forgot Neil Young.

Topic - note that the kit in the bulletin used 4 x 90 mains and therefore abandoned the front / rear thing and then Honda did the same for 2005 (4 x 90) before bringing it back again (but opposite) in 86 for the CA model.

 

You didn't hear about the 2005 VFR 500? Hmmmmm, that would be very cool. Sorry for the typo! 1985

 

#90's front and back and different jet needles too...

As noted this was for hot start issues. I would think #102F/#105R would be a better setup, if the engine can handle it, why not. But then again not being able to start your bike after fueling up would be a bit of a bummer.

 

Well, I have no proof this is not a CA bike, but I did have 95f/92r jets in mine. Is there any way to tell from the VIN if it's a CA bike? There's nothing on the VIN plate that would indicate it.

To further add to the confusion, the Factory Pro recommended settings for the CRB-H13-1.0 kit say the following:

CA w/stock pipe: 88r/90f
49 w/stock pipe: 92r/95f
w/aftermarket pipe: 98r/100f

The sheet also states the pilot jet is #35 for CA bikes and #38 for 49 state bikes.

 

Here ya go: