Rough running FJ1100

[Gord]

As soon as I have finished doing my winter jobs on my YZF750 street fighter, I'm going to make a start on my FJ1100 trike 

It needs a bit of TLC, I haven't had a close look at it yet, it's been stood for we'll over a year, it starts after turning over and spluttering for a while.
Once it's started it runs really rough, and quite high revving, it stinks of fuel as if it is really rich and doesn't rev smoothly at all.

I have took the carbs off, I'm planning on stripping and cleaning them, changing oil pugs, filters and putting new fuel in etc. I have never stripped carbs down before, any tips?

I've noticed that you can buy K&N type air filter pods really cheap, do the FJ engines run OK with these fitted or am I best using the original air box?

Any tips or comments are more than welcome.

[FJmonkey]

The carbs will need a good cleaning, spot on there. Many here have had problems keeping the K&N single pods on, and they don't filter as well as the UNI dual pods. I recommend the UNI dual pods as I have had zero issues with them over the last two years. But if you are in a financial bind then any filter (panty-hose stretched over the intake) is better than none. Make sure the carbs are really clean, ultrasonic clean, the idle jets are really small and hard to get the crusty old gas out. Good luck, keep us posted.

[RD56]

Gord, I'm a month new to this board and can't begin to tell you the depth and breadth of the knowledge that these unselfish guys provide. I have a 1985 FJ that sat for 8 years on it's side stand with gas in the bowls and tank. When it comes to carbs, besides info from members the best links for me were the Mikuni Guide: Mikuni_BS_CV_Carburetor_Rebuild_Tutorial.pdf. There is also some fabulous stuff that you can access in the files section re: cleaning, carb specs. I'll try to put a list of links together with some of the stuff that I found. There's a great write up by Michael B. about function of the Mikuni carbs found on these bikes. The most important thing is to have a modicum of mechanical common sense and then be extremely organized after doing all the due diligence required. Ask as many questions as you need PRIOR to operating on the heart of your bike. Use RPM for yours parts source and you can't go wrong.

I completely disassembled my carbs wihout buggering one screw, jet or float. But I took my time and studied everything I could get my hands on. The biggest problem that I had was removing the float seat. The reason that I mentioned that the bike sat on its side stand is that the #1 carb is on that side, so all the nasty crap that the 10% Gov't additive to our gas, accumulated in that bowl and its inner workings. It was stuck in concrete, literally. Soak and let sit with Blaster, and some of the best advice was to simmer in distilled water for 30 minutes to take advantage of different thermal characteristics of brass and aluminum. Finally got it out, but you would not believe what crap was holding this thing in place. Also got a tip from Maestro Condon to find the shank of an old drill that fits snugly in the seat assembly so that when you grab it with whatever "grabbing tool" tool you are using that you do not crush the tube. This is a start, from my perspective anyhow. Use this crew of Irreverent Bastards and you will not go wrong. Don't listen at your own peril!!

One last tip: inexpensive Pine Sol, Original formula, worked wonders. I didn't use any expensive carb cleaner and got fantastic results. A buck and some change.

Good luck, Rick

[Pat Conlon]

Thanks for the kind words Rick.
Kinda of funny, the spelling of my last name....I've been a customer with Bank of America for about 40 years now. I went online to re-order a box of checks, no problem. I know what you're thinking, who uses checks anymore? The next week a box of 500 checks arrived made out to Pat Condom..WTF?
I called their 800 line and explained the situation, the nice lady tried tried very hard not to laugh, but I could hear snickering in the background. She assured me that B of A had the correct spelling of my last name but she needed me to take the box of checks down to my local Palm Desert branch and show it to the customer rep.
The nice young lady at the local branch turned beet red when I explained that "I don't have to worry about safe sex....I am safe sex.."

[FJmonkey]

Errr... Not with USD forks and the shine you have on your 84'. The chicks should be surrounding you like a zombie horde... Like the Resident Evil movies... Just saying...

[Joe Sull]

I found a utube video on the carb cleaning that I don't think is in the archives. It's kinda of a 101 video. If one of the senior members could look it over, it my be worthy. I am using the "Mikuni carburetor operation..[1].pdf" from the archives and I think it's great.
Here's the link
http://www.youtube.com/watch?v=95nlrP-yn2I

[RD56]

Personal post to Mr. Conlon. I was too lazy to go back and check, what do you want from someone from the wrong coast? Sorry Pam. (Meant to be funny Pat).

[Pat Conlon]

No worries Rick

[Gord]

I've stripped and cleaned the carbs, refitted them and started it up with some fresh fuel.
It starts great and sounds ok on tickover, but as soon as I rev it, it won't rev very high and it spits back through the carbs and the exhaust. It sounds really rough, any tips?

[FJmonkey]

Have you balanced them yet? They will be off after a service like that.

[movenon]

Good morning ! Wow that's a loaded question. You indicated the bike had been in storage for a year, running rough and needed some TLC. Is the bike new to you ?  Was the bike ever running good while in your possession ? Sometimes if you post where you are located other FJ owners close by can help out. Also as mentioned by I think Pat (?) is to, in your signature post the year of bike you have.

Just from reading your post I would start with the simple things first. Double check your fuel feed lines, the routing is very important with the gravity feed models. Double check your plug wiring (you indicated you were going to change plugs). Did you do a blip test to see how the tach/rpm's act when returning to idle ? Is the choke working correctly ? Those rubber boots on the intake to the engine side, make sure they are on the carbs correctly. They are hard to check especially on the bottom side. Sometimes a little starting fluid squirted around the area will give you an indication of an air leak. Be carefull with that stuff and don't start a fire.....

Those are a few surface things to check. If the bike was new to you did you get a base line compression test and check the valve clearances ?

Hope that will get you started  
George

Like FJmonkey said also... balance the carbs. 

[FJ_Hooligan]

Idle circuit is still clogged.  Did you remove the idle jets AND the mixture screws?

[Gord]

I cleaned both, however I had not fitted the petrol tank or air filter.
I noticed there was no vacuum pipe on No1 and No2 carb had one which was not fitted to anything.
Would this cause the carbs to suck in air and back fire?

[Pat Conlon]

Yep, that will do it. The vacuum port on #1 goes to your vacuum petcock. The vacuum port on #2 goes to your ignition box for the vacuum advance. #3 and 4 are plugged.

[movenon]

Yep, that will do it. The vacuum port on #1 goes to your vacuum petcock. The vacuum port on #2 goes to your ignition box for the vacuum advance. #3 and 4 are plugged.

Then adjust the idle to 1150 RPM, adjust the fuel air screws (blip test) and sync the carbs.   See where you are after those adjustments.
George