Topic: PD46C tuning

[AlekStooge]

So I was doing it right don't put pressure on the valve when measuring and basically try to keep it parallel to the bowl. In that case (I know its hard to tell with pictures) the heights are right in the first three pics. I going to do the clear tube method what diameter tubing do you have so I know what to get at the hardware store? It looks like you're attaching it to the overflow

[DaveBarbier]

I honestly don't remember. It's the same as your overflow tubes. I would just measure the overflow nipple to be sure.

If you don't know how to do the clear tube method then look it up, it's all over this site, but it's pretty self explanatory by looking at my picture. Not rocket science.

[harisuluv]

And why does your #1 pilot jet have a slot in it.  Why would a press in jet have a slot in it. 

[AlekStooge]

The pilot came like that I've bought a replacment that I haven't put in yet.So I should just stick to the clear tube method and adjust till I get to 4mm. Thanks

[AlekStooge]

I'm ready to fire the bike up this weekend. Below is an exerpt of my original post. Some things have changed. The carbs have been rebuilt, ultrasonic cleaned and bench synched. See project here which I have to update.
http://forums.sohc4.net/index.php/topic,183457.0.html

The engine has been rebuilt as well . MJR head ported. OS intakes, 126-00 megacycle and switched to Dyna coils after C5 coils turned out bad. Compression was very high and even across all 4.

Today, I am going to check valves and ignition timing was set after cam installation. Other than that the set up hasn't changed. I have gotten genuine main jet sizes 100-110 and pilot 42-45. And... a whole lot more experience working on motorcycles.

Today I'm starting to set up my carbs. Here is what my set up is going to be and what information I gathered from the forum in doing this correctly. I know Honda engineers decided that the stock air box is truly best for these bikes and I'm going against what is recommended by the forum members. I've heard it before on here so I don't need to hear it again but clearly there is a way to correctly tune for individual filters (opposed to just throwing them on and expecting it to run smoothly) and I plan to do so with the information I've gathered. Please tell me if I'm on the right track and what I can do to make the process more through and results more accurate.

Here are the details of my setup:

PD46C carbs
MAC 4into1
Main jets 105s ( I have 108s in case)
Pilots stock 42s ( I was told not to up these to 45 as the aftermarkets don't live up to the originals quality and the IMS can be tweaked to compensate)
IMS one turn out left
Shimmy the needle to the third setting from the top.
Adjust the floats to about 12.5mm or at least have them close and all equal.
Chicagoland elevation no other adjustment needed. 759ft above sea level at the local airport.

What order do I make these changes. I have a pen and notebook ready to record results, I just don't know which one to start with? I don't want to do all of them at once, so I can avoid ambiguity.

I used this page on the forum http://forums.sohc4.net/index.php?topic=98867.0 as well as Denny Zanders jetting guide for my info.

I would like to confirm the PD46C float height is 12.5mm? There are some posts on here saying 14.5mm which I believe is the PD46A stock.

Anyways thank you for reading all this. The intention here is to gain experience tuning, reading spark plugs, making the correct adjustments and receiving guidance along the way. First course of action is to start the bike, check for vaccum leaks and synch.

First question when you make adjustments do you make then one at time for a given carb circuit and record results or could you adjust multiple variables?

[Floshenbarnical]

Anyone on here use a Wide Band to tune their jets or do we all do it with plug chops and seat of our pants? I've been wanting to buy an Innovate LM2 for years. Maybe its time. Also, has anyone tried to weaken the throttle return spring at all to ease up the throttle pull?

I'm taking a loop off my throttle return spring this winter, the hand cramp is awful

[bryanj]

Taking a loop off will make it tighter and more difficult to turn