Hi all,

I picked up a 1995 F3 about a week and a half ago. Took a basic overhaul to get it started, new plugs and oil and some spray carb cleaner, but now it starts up right away. The guy I bought it from only owned it for a year and used it as a commuter, but after examining it I'm certain that someone before him stripped it down as a track bike. When I got the bike, it was missing the D.A.I. Duct including the elbows (air box was open to the elements) and both solenoid valves. I was also told that it has a stage 1 jet kit installed. I since bought the D.A.I. Duct off eBay ($30) and installed it (which was a pain in the ***). The air filter is stock, it has a Yoshimura exhaust, and its geared 14/45 (-1/+2).

Before installing the new duct, I noticed that it would idle at sort of random speeds- sometimes 3, sometimes 4.5. This was while I had turned the idle speed to about 1.75 while it was warming up. It was also giving me inconsistent power delivery, sort of pulling as it saw fit. It still responds faithfully to the throttle, but rather than getting a certain amount of power at a certain throttle opening, I get a fluctuation between a range of power. This is much more prevalent when cruising downhill or otherwise at idle throttle, when the bike sort of pushes and pulls randomly. I assumed that installing the duct would be the first step to smooth out power delivery, but it seems to have done nothing at all and possibly made it worse.

I've since loosened up the throttle cable which I'm pretty sure was too tight because of having to route around the new elbows, but haven't had a chance to do another test ride because of the snow, but I suspect this will help with the idling.

My question is, what else can I look at to help smooth out the power delivery? And if the bike was tuned to run the way it was set up, should I have just left it alone?

 

Can you post a pic of your air nox and hose layout? Could possibly be an air issue. After that you prolly need to do a carb clean & sync

 

Everything you're describing here is classic dirty carburetor symptoms. What all did you do to the carburetors when you used the spray cleaner ?

 

I don't have a good picture of it, but basically the hoses that normally go to the solenoid valves just go straight to wherever they go after that (carbs?), and the solenoid valves are missing.

For the carbs I just pulled off the bottom of the air box, pulled the needle back and sprayed the honda carb cleaner on/in the needle/jet. I didn't take them off to clean because I don't think I can resync them at home.

Update: I took a spray bottle to the exhaust manifold and I'm pretty sure cylinder 2 isn't firing. I think it was when I first changed the plugs, which would explain why I didn't notice the power loss at first. I'll pull the plug out when it cools off and take a look at it. I can get a picture of the air hoses then.

I'm just doing this in my garage which is ill equipped... Not sure what I'll do if I have to clean rings.

 

as idodirt said the problem more than likely lies in your carbs. just spraying carb cleaner at them wont do much.
you'll need to take them off the bike, and take them completely apart and clean everything.
it can be quite difficult(to reassemble at least), so if youre not up to it id find a friend than can, or take the carbs to a shop...but that will be $$$.

 

If you want to do a complete rebuild of your carburetors, this is a list of what you'll need to replace all the O rings and gaskets. This includes the float bowl, drain, AF mixture screw, Air Cut valve, Fuel Supply T's, Vent T's, Needle Jet Holder, and the Air Box to Carb.

Then you need an afternoon to do the dissassembly, cleaning, and reassembly. Replacing these parts and doing a thorough cleaning should have your carburetors performing like new. Buy your parts anywhere, this is just an example. This is only rubber parts. No jets or needles or anything like that.

 

Btw, everything you need to properly clean carbs can be found in a garage capable of changing the oil in any vehicle. No special tools required

 

The cleaning I'm actually fairly comfortable with, I found a few good how-tos on here. Will it run well enough before syncing for me to ride it to the shop, or will I have to trailer it? Honestly worst case scenario is I pull the carbs off and they're totally clean.

 

I don't know If the carbs on the f3 are like the f4 but I've cleaned just the slow and the main jets several times and it would restore smoothness and run better. Yesterday I took out the pilot screw and clean it for the first time in sixty thousand miles! When test rode it it was literally a different running machine! The throttle is so crisp and snappy now. I never knew it could deliver power like this.

Next is a sync tool for sure. I want to completely disasemble and dip the whole rack and let it soak over night to get it super clean. I'm hesitant because of having reinstall the throttle sensor. I don't want to learn how to do that yet. I have a "if it aint broke don't fix it" mind set on most stuff.

Point is, My experiance with carb tune ups; go all out. You will not regret it at all.

 

if you can clean the carbs then you can sync them as well, its really not that difficult.