85 Vf500 idle/choke issues?

I didn't hear any tapping. It's only got 13K on it...time for a valve adjustment already? What's the interval?

I've never done a valve adjustment on a V4. Seems like a PITA, yes?

 

7.5k

Honda recommends the first valve adjustment at 7,500 miles. If you don't know if your bike had this service performed then it might be a good time to check them while you have the carburetors off.

 

oem

It's noted in the Factory Manual's Maintenance Schedule. I was actually going from memory on the 7,500 but I looked this up to double check and officially my '84 Manual notes:

Valve Clearance Adjustments

• 600 mi
• 8,000 mi
• 16,000 mi
• 24,000 mi

On the soapbox for a minute - I have both the Factory and the Clymer Manuals - the Factory is way better. These come up on eBay every now and again for a reasonable price and often you can get them with the original spiffy green Honda binder. Well worth the investment!

 

Update:
Just went out and #3 and #4 still had carb cleaner in the clear tube. Took a .012"/.30mm new guitar string and fed it down the enricher tube. Kinda hard to tell since I couldn't see what I was doing and had no idea what the bottom looked like, but eventually with small taps of the string I found a hole/slight indention/bowl. I marked the string with a sharpie, and moved along the line.

This helped a lot. On first pass I got 1" into each tube. Then, it sank a bit deeper (about 2") into the #4 and the #2 tube. Filled the clear tubing with cleaner again, and this time all 4 slowly went down into the enricher tubes.

I gotta say, if you're having to do this, using the clear tubing over the enricher tube filled with carb cleaner is the only way to go. Immediately lets you know if you're clogged or not. I thought I was home free till I tried that trick. Saved me a lot of work having to pull the carbs twice.

So...NOW I think I'm good to go. Wonder why only a few allowed the guitar sting in a full 2"? The rate of carb fluid entering all 4 enricher tubes seems to be consistent, i.e. none seem less clogged than the others according to the rates at which they all took the same number of sprays. String came out straight in all 4 as well, so it isn't bending around into another orifice tube. Hmmm...

 

I'll take a look @ the SM in regards to valve check. I've done them on my ZX10 myself, but that's a simple in-line four with shims under the buckets.
If only there was a list member who had done it before near the northern part of The OC.. If only....

 

These bikes generally hold valve adjustment for a long time. If the bike is new to you, I would do it to be sure. If they are too tight it is a silent killer. The first time I did mine, it was noisy as hell afterwards. Paid a visit to the dealers service dept. and found out there is a special honda tool that you slip over the end of the camshaft and pulls the cam up against the top of the cam holder. Viola! Works like a champ. The only other trick is to use a feeler gage under both valve stems and adjust for equal drag. Mine has 41,000 MI & have done all maint. since new.

 

1snotenuf - Welcome to the forum!!


The general consensus in the V4 community is that the Honda tool to pull up on the cam actually does more harm than good. It was a stop-gap fix in the hopes that people who stop complaining about top end failures. Since it didn't address the problem, the complaints continued.

I've never used the tool personally and have always been able to set the valve clearance accurately. It's fairly tricky to get it right and often takes several tries per valve before it's set. What helps a lot is to use two feeler gages of the same thickness (the desired setting). That way you can set both valves on that rocker arm at the same time. This seems to work a lot better than the cam holder tool.

In case you are wondering, it's my understanding that well-known V4 engine builder Dave Dodge does not use the cam holder tool.

 

That's the process - I forgot what it was exactly. I knew that he didn't use the 'pull-up' tool. Using one feeler gauge might be easier, I've just always used two. I'll have to give Dave's method a try next time.

 

I read in my recently acquired Honda Service Manual that the Pull-up tool should NOT be used on 1986 VF500 models.

 

factory manuals

An interesting note regarding the '86 manual - thanks for posting.

The '84 Honda Service Manual (issued in '85) definitely recommends using the aforementioned tappet adjusting tool (part no. 07979-MK30000).

I wonder if this is due to the difference in the engine design? Good for the '84/'85 but not for the '86?

 

My understanding behind the whole cam holder tool was that it's purpose was to take up any possible excessive clearance between the cam and it's bore. This was because the early VF engines had the cam journal caps machined separately from the heads, which are the other half of the journal. The 86 VF500 engines were lined bored and therefore did not have the possibility of clearance issues.

Again, the whole thing was a stop-gap just to keep the public calmed down and didn't really fix (or hurt, really) anything.

 

valve adjustment - different techniques

Here is a well written post regarding valve adjustments for the early V-Fours on the FAQ page of the SabMag site. The author details two methods one by Dave Dodge the other Robyn Landers.

ValveTrain/ValveClearanceAdjustment - SabMagFAQ

I can see where you wouldn't necessarily need the tappet tool for the'84/'85 VF500F (using the 'Dave Dodge Method').

At the same time it does look like it can help dial things in when using the 'Robyn Lander's Method':

Motorcycling -- The Honda V4 Files and More

 

I was a current Honda tech back in those days (still am BTW). At update schools and talking to different techs it was about 50/50 tool or not. Seems everybody had a slightly different formula. I personally had the best results using the cam holder tool and setting at .005 inches...and I've done dozens of 'em. You WILL get very different measurements using the tool or not depending on the cylinder you're measuring.

Honda came out with the revised adjustment procedure back in 83, including using the tool and increased clearances...if I'm not mistaken from .002 to .005. I think the main reason for the tool was for consistency. On some cylinders, the adjacent cam lobe is opening a valve, some not...thus a slightly different static force pushing the cam whose lobe you're trying to measure. Because the cam bearing oil journal clearance (Jamie mentioned this) is pretty sloppy on the older V4's...it can make a big difference in your measurement. Is that freakin' confusing or what? I always thought it was.

The main criticism I heard for 'using' the tool, is that on cam bearings that are very wore it would make it easy to get one 'too tight'. Guess I always thought if that were the case, valve adjusment which was only confusing would become downright 'voodoo' like. And the cams and heads weren't long for this world anyway.

I concur that the 86 V4's are line bored oil journals, and valve adjusment for this year didn't require the tool. In addition...starting in 86 Honda began running oil through the filter, instead of directly from the crankcase sump up to the head (haven't confirmed this with the shop manual for all the V4's but that info came directly from Honda so it's probably good). The reason being for longevity (less particulate matter floating around the head).

 

I'm 99% sure the 86 VF500's also had unfiltered oil going to the heads. The only oil system change was a different relief valve to bump up the oil pressure.

I wonder if there is a way to [easliy] confirm or deny this.

 

There is...the OE shop manuals have a special section for lubrication. There is always a diagram for oil distribution. Assuming that info is correct it should reveal the answer.

I was told this at the annual 'update' school Honda had for the new models. That was twenty years ago and I'm counting on my memory. It may have been in reference to the bigger V4's. The 500 could've been left out. Maybe Honda felt the other changes were adequate for an engine in it's last year of production anyway.

 

squirrelman, do you mean that the main jet and slow jet both have to be turned back 2 and a half turns? Could you describe in more detail how the two pieces that comprise the main jet are supposed to be, as well as how the slow jet is supposed to be (how many turns etc)?