81 SH project

[motoman]

Thanks guys,

Is the 3mm from the surface between the bowl gasket and the carb body (like the measurement for the floats themselves) or is it from somewhere else?

I feel like a schmuck. When I set my float heights, I neglected to hold the float to the float needle. I'd imagine my measurements are all +/- 2mm because of this mistake.

I went to harbor freight today and picked up a viton o ring kit to replace my float seals (mine have seen better days). I haven't replaced them yet. Would a leaky float o ring also cause these high rpms while using the enrichener circuit?

Ed

Answer to your first question is you'll be measuring the actual fuel levels from outside carbs. (May re-read how I stated that is done).

Secondly, haven't a clue what you mean since the float rest on the float needle.....then measure UP to highest point of float. Whatever you've done, things are way farther off than the couple millimeters. I suspect your just guessin' anyways. (close is NOT good enough for the later carbs).

Thirdly, since your just guessing at this point, replace those push-in seat O-rings, and set the float levels at 23mm. Any internal leaking that raise fuel levels can cause higher rpms.......to the point it just floods, dies, and fuel runs out of carbs AND forward to combustion chamber and into crankcase, which if not known WILL trash bearings if continued running.

If you haven't removed slides to access and remove emulsion tubes and cleaned all that spotless along with pilot jets and cleaned them plus inspect the internals of them for a left 'science project' with a magnifying glass, the carbs are NOT clean ..........your just chasing your tail, and possibly in just way to big of a hurry to wanna ride it. No offense intended, just a wild guess.

[phatts27]

I used a metal mm ruler to set my floats. I watched this video on how to adjust the heights and used my supplementary manual to find my specs. At the 5:20 mark he's talking about making contact with the float valve. Bad info? https://www.youtube.com/watch?v=v08XqhdwAbo

My carbs are clean I swear!

[motoman]

I used a metal mm ruler to set my floats. I watched this video on how to adjust the heights and used my supplementary manual to find my specs. At the 5:20 mark he's talking about making contact with the float valve. Bad info? https://www.youtube.com/watch?v=v08XqhdwAbo

My carbs are clean I swear!

just invert the carb bank minus the gasket, measure to highest point of float, no need to touch the float. If that concerns you, angle the carb bank a bit to take float load off spring loaded needle(to my knowledge, hasn't been an issue for others). Set that height at 23mm. To know RUNNING fuel levels are correct, your still gonna have to 'hose' them, looking for the 3mm down from carb body flange, which IS the factory procedure for your year carbs. Any fuel level variences need to be noted, how much and on what carb. At that point, don't mix up floats with needles, as they need to stay with same carb they were removed from for any adjustment changes......bowls back on, repeat running level check. Like I said, your gonna be a pro at quick carb removal/installation by time you reach the point of final idle mixture settings and sync.
The later carbs just don't seem to be as forgiving to human error as the earlier 78-79 carbs having the cross-over drawing fuel from both circuits at same time.

May wanna also check voltage going to the coils with key on. Should NOT be any drop from what battery shows on a meter when key is on. Curious to know those voltage numbers.

[phatts27]

Checked the voltage. 11.75 on the battery. Coil #1 11.20. #2 11.19. I tried to get the battery ground off to clean it up and I broke my driver. Primary ohms were both 2.4. I must be doing something wrong to check secondary because I wasnt getting a reading from either side.

I replaced the o rings for the float valves and used some brasso to shine up my float cup, not the plastic float itself. Put the tank to prime, pull enrichener all the way out and she idles at 2500ish then starts to rise after about 30 seconds.

[phatts27]

by the way, the right petcock is fine. It only work on prime because I was almost out of gas.Doh'!

[DiverRay]

Specials DO NOT RUN WELL low on gas! I found I need about 1.5 gallons in the tank to be able to set anything.

[motoman]

Checked the voltage. 11.75 on the battery. Coil #1 11.20. #2 11.19. I tried to get the battery ground off to clean it up and I broke my driver. Primary ohms were both 2.4. I must be doing something wrong to check secondary because I wasnt getting a reading from either side.

I replaced the o rings for the float valves and used some brasso to shine up my float cup, not the plastic float itself. Put the tank to prime, pull enrichener all the way out and she idles at 2500ish then starts to rise after about 30 seconds.

Looks like my suspicions are verified.The battery voltage is on the low side. Even with key on, which activates the two idiot lights, tail light and front marker lites, voltage should still be in the 12.2-12.5v range at the battery. Fully charged when new would be in the 12.7-13.2v range. This is one issue that is gonna affect lower rpm voltage output to the coils. Voltage drop at coils compared to batt. Voltage drop isn't bad enough to cause an issue.......yet, but will. Ignition and kill switch complete that circuit. Removal, dissassemble kill switch in a baggie so tiny spring doesn't get ate by man-cave. Dump all pieces including the switch in a jar of EvapoRust overnite. Wash clean and dry. Add a dob of dielectic grease and re-assemble.(Evaporust makes plastic colored insert bright again).

The coils were originally 3ohm. The cut-off point IMO for them failing is 2.7ohms, specially at lower charging rpms. Yours are 'whacked', and WILL cause incorrect tuning while idling. No reading secondary is a good thing.
As a side-note, I had exactly what you have goin on voltage wise and failing stock coils(two different sets @2.3ohms). Now have a set of Honda VF500 coils on which are plug and play, plus gives me a choice of secondary ignition plug wires. Best part is tuning mixtures at idle are correctly set instead of unknowingly compensating for a weak igniting spark.

The idle reaction with enricher full out is normal. Knocked back in to the first position should put it in the 1500rpm range till motor is operating temp, at which time idle will rise again till enricher is off.

Bottom line is primary and secondary ignition issues have to be resolved before any suspect fueling issues, or you WILL be chasing your tail.

[phatts27]

You are correct sir, the coils are reading a bit low. I checked eastcoasters parts bike's coils and found that one was 2.7 ohm, the other 2.4 ohm (still couldn't get a secondary reading from either). The battery is less than a month old and still on its original charge. I've only let her idle with a twist of the throttle here and there so I'd imagine the battery isn't getting enough juice to recharge adequately. If, when I clean my switch internals, I find I'm still losing voltage to my coils, where would be the next place to look, the harness itself?

As far as replacement coils go, should I be concerned with more than just finding 3ohm dual posts? New and cheap is my flavor. I read here that the knockoff green coils from Mike's won't last too long and at $85 apiece, I'm sure I could find a better deal. Where did you source your vf500 coils?

I have new mikuni pilots 42.5 and mains 110, 115 coming in the mail. You are right, I need to make danm sure the spark is adequate before I start tuning. Right now, the jets are all no-name. Plan is to revert to the stock jets and go from there.

On a side note, I road the beast for the first time today. I only went across the street to get some air in my tires but she sounds mean. This is a whole lot of bike.

[jetmechmarty]

If you're buying new coils, get something good. Z1 has these at $130 for a pair.

[crazy steve]

+1 on the Dynas.....

[motoman]

You are correct sir, the coils are reading a bit low. I checked eastcoasters parts bike's coils and found that one was 2.7 ohm, the other 2.4 ohm (still couldn't get a secondary reading from either). The battery is less than a month old and still on its original charge. I've only let her idle with a twist of the throttle here and there so I'd imagine the battery isn't getting enough juice to recharge adequately. If, when I clean my switch internals, I find I'm still losing voltage to my coils, where would be the next place to look, the harness itself?

As far as replacement coils go, should I be concerned with more than just finding 3ohm dual posts? New and cheap is my flavor. I read here that the knockoff green coils from Mike's won't last too long and at $85 apiece, I'm sure I could find a better deal. Where did you source your vf500 coils?

I have new mikuni pilots 42.5 and mains 110, 115 coming in the mail. You are right, I need to make danm sure the spark is adequate before I start tuning. Right now, the jets are all no-name. Plan is to revert to the stock jets and go from there.

On a side note, I road the beast for the first time today. I only went across the street to get some air in my tires but she sounds mean. This is a whole lot of bike.

Got the VF colis locally as I wanted to be able to test ohms prior to purchase.
Overall, coils used on Hondas seem to stand the test of time better than others, without breaking the bank finding them used.

If you were to pull the slides, un-clip and remove the metering rods, you'll find near the top on side of metering rod numbers and letters. Using a magnifying glass(for these ole'eyes), stamped in it will likely be 5GL16, which were the metering rods used in the 80-81Specials, which used 110mains across all four. The staggered jetting was used on the 81Standard(Venturer), which had different metering rods, and with the added load and slight air flow restriction to center cyls. due to the factory installed oil cooler, the bit richer mains helped keep cyl. temps. down. It could end up a bit on the rich side for those center cyls., as that is two steps from stock.

[phatts27]

Thanks guys, green coil's in the mail. Motoman, I wasn't planing on using both mains at the same time. I purchased (4) 110 and (4) 115. Mine are the 5gl16 (I know this because 1 was wrong (it was too short), I had to get 1 replacement. I will need some larger pilots probably because I'm using k&n cone filters.

I see brillman offers new-old style copper core, cotton clothed, non suppression, 7mm ignition wires. I love the style. I talked to their rep and he said they should be fine for my application. Does anyone know where I can get just coil boots and coil-side leads for the dyna coils? Should I just get the recommended 7mm wires on the Z1 site? These have the coil-ends and boots.

[phatts27]

Hey guys, I found the terminals and boots on brillman also, just had to dig a little deeper into their site. I'm planning on getting these. Any advice?

https://www.brillman.com/store/produ...coil-boot-1999

https://www.brillman.com/store/produ...l-terminal-139

https://www.brillman.com/store/confi...-the-foot-1836

[phatts27]

Good call on the dyna coils, they are awesome. I can feel the increase in pressure coming out of my tail pipes from just these coils. Installation was easy enough. The hardest part was sliding the boots around the ignition wire. Mounting the coils so they didn't contact the frame proved to be a bit of a task, but a trip to the hardware store and a little metal work performed with a BFH did the trick.

I removed the entire harness again and let it soak in white vinegar/ salt for a few days and then neutralized it with some baking soda and water. After that I let it dry for a day, flipping it here and there to let the sunlight do its thing. I gave a generous helping of dielectric grease to every connector and plugged everything in. Unfortunately, it was getting dark as I was finishing up and I wasn't able to check my voltage at the coils. I'm hoping for no drop off from the battery this time.

Next thing to do is find why my signals and brake light don't work. Looks like I'll be at it with the multimeter again (oh joy).

[jetmechmarty]

dielectric grease is an insulator

As written by Wayne Orwig, MGNOC Georgia State Rep.
Quote:

Using Dielectric Grease on connectors.

A lot of people use dielectric grease on connectors. Some people mistakenly believe that dieletric grease is a conductor. In fact, it is just the opposite; it is an insulator. Dielectric grease is typically made of silicone grease.

As an insulator, dielectric grease is good for use on spark plug boots. This was one of the original applications on vehicles when the high-energy ignition systems came out. It can help insulate the connector and, in particular on a motorcycle where it can get wet, it waterproofs the spark plug boot. And, because it is silicone, it is fairly stable at high temperatures and won't affect the rubber and plastics.

So why would you put an insulator on a connector? The idea is that you use a thin layer. When you push the connector together the grease is pushed out of the way enough to get a connection and the surrounding grease then keeps out water and oxygen. The connector will be protected from the environment and less likely to corrode. Plus, the silicone is safe for the plastics and PVC insulation.

That sounds good, so far; so why not smear it on everything? Well there are a number of good reasons.

First, silicone grease outgases constantly. If the silicone gas gets near a connector or a contact, such as a relay, and there is a spark, the spark at the contact can create silicon dioxide. Some people even suggest that the silicone gas from dielectric grease can travel many feet through the unsulation on a wire and damage a contact on the other end. Omron states that even their sealed switches can be damaged by nearby silicone grease outgassing. Reference the following links for more info:

http://www.omron.com/ecb/products/pdf/en-d2vw.pdf

Lubricating electrical switches | Archive content from Machine Design

Second, it is an insulator. It can prevent contacts from touching. If you do use it, use a very thin layer.

Third, if you have a corroded connection, silicone grease will not help. In fact, it may make it worse. It can never improve anything. Dielectric grease will never make a poor connection better.

Fourth, it attracts dust and dirt and it hardens over time. This means that if you smear a lot of silicone grease on connectors you may see nearby relays, switches, or points fail later on. Since silicone grease does nothing at all to improve the connection and, in fact, may insulate the contacts in the connector increasing the resistance the connector may still fail.

So what do you do? Look for a contact enhancer/lube. While most contact cleaners are simple solvents that just wash the connector off there are contact enhancers that deoxidize the contact surface and actually work to lower the contact resistance (make a better connection). Most contact enhancers leave a lubricant behind that protects the metal and continue to deoxidize the metal and improve the connection. They can work to lower the resistance and make a better contact as time goes by. The best you can hope for from dielectric grease is that it seals it enough to not get worse. I have used Caig Deoxit on my bikes for a few years now. I first found out about this on my job when I had to correct an issue in a connector system that could not tolerate even 5 thousandths of an ohm of resistance drift. We had a connector in the field that had been improperly plated and was starting to drift, mostly in warm humid areas like Florida. Our testing showed that the Caig Deoxit could be a good long-term fix. We ended up using the Deoxit to stabilize the bad units until we could get corrected wiring harnesses built with the correct connectors. We also put a layer of Deoxit on the new parts to protect and keep them clean over their lifetime. This solved the drift issue that we had.

I still use a small amount of silicone grease on my spark plug caps. It helps to waterproof them and makes it easier to pull the cap off, but I use it in very small amounts and never near a relay or switch.