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Easily missed

Started by ribbert, March 03, 2014, 05:33:05 AM

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ribbert

This might be of benefit to some. I don't believe I've ever seen this referred to here.
Last night I went to re install some FJ carbs I had removed earlier in the week and it was immediately obvious how difficult (near impossible) the air box would be to refit. As if it's not bad enough already.

These boots are non concentric with the holes in the air box, so, as you rotate them their position changes, up, down, left and right, individually.

These lugs locate them in the correct position to line up with the carbies. If they are not lined up it makes a difficult job even harder, or, even impossible. The boots on the one I removed showed signs of stretching and were so far out I have no idea how they were made to fit.

The lug on the boot sits between the lugs on the box.



Noel
"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"

baldy3853

Noel the correct way to fit an air box is hold it in your right hand cock your elbow and throw that F@@@er as far across the Street as you can then mount pods....... Problem solved  :rofl: :rofl: :rofl:
Baldy

ribbert

Quote from: baldy3853 on March 03, 2014, 08:33:02 AM
Noel the correct way to fit an air box is hold it in your right hand cock your elbow and throw that F@@@er as far across the Street as you can then mount pods....... Problem solved  :rofl: :rofl: :rofl:
Baldy

You're absolutely right, but it wasn't my bike. I had forgotten what a bastard of a thing they are to refit.

Noel
"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"

Dads_FJ

Quote from: ribbert on March 03, 2014, 08:45:14 AM
Quote from: baldy3853 on March 03, 2014, 08:33:02 AM
Noel the correct way to fit an air box is hold it in your right hand cock your elbow and throw that F@@@er as far across the Street as you can then mount pods....... Problem solved  :rofl: :rofl: :rofl:
Baldy

You're absolutely right, but it wasn't my bike. I had forgotten what a bastard of a thing they are to refit.

Noel

Did you pivot the sub-frame back?  The time is takes to perform that is well worth it and makes installing much much easier.
John S.

'84 Yamaha FJ1100
'89 Yamaha FJ1200
'94 Yamaha WR250
'80 BMW R100S/Sidecar
'39 BSA WM20

aviationfred

I removed the airbox once and re-installed it.  :ireful: :mad:. Like I said....ONCE. I have since subscribed to the "The Baldy Method" of airbox installation.... :dance:

Fred
I'm not the fastest FJ rider, I am 'half-fast', the fastest slow guy....

Current
2008 VFR800 RC46 Vtec
1996 VFR750 RC36/2
1990 FJ1300 (1297cc) Casper
1990 VFR750 RC36/1 Minnie
1989 FJ1200 Lazarus, the Streetfighter Project
1985 VF500F RC31 Interceptor

movenon

Did about the same as Fred.  In the the end it was UniPods.......  Notice a lot more room ?



George
Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200

DB Cooper

I haven't had to remove the air box yet...... Do unipods require re-jetting?
Kevin
I remember when sex was safe and skydiving was dangerous.

movenon

Quote from: DB Cooper on March 03, 2014, 01:48:07 PM
I haven't had to remove the air box yet...... Do unipods require re-jetting?
Kevin

I can't speak for everyone but I didn't re-jet just for the pods.  I did re-jet a while back when I rebuilt the carbs from 110 to 112.5 jets and went with adjustable needles.  I am at 3000 feet.  Not a big change.  My bike is a 1990.  I think the early bikes might already be 112.5 mains.
I vote no on re-jetting just for unipods.  At least don't worry about it until its a problem..... You would have to run it at wide open throttle and do a plug read to test.

George

Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200

TexasDave

 I had pods installed on my 84 and it doesn't run like it should unless I apply a "small" amount of choke. When this is done it runs great all the way to redline. I think all it needs is the needles shimmed or adjustable needles. What do you gentlemen think?  Dave
A pistol is like a parachute, if you need one and don't have one you will never need one again.

movenon

Quote from: TexasDave on March 03, 2014, 02:14:16 PM
I had pods installed on my 84 and it doesn't run like it should unless I apply a "small" amount of choke. When this is done it runs great all the way to redline. I think all it needs is the needles shimmed or adjustable needles. What do you gentlemen think?  Dave

No expert on carbs other than I have rebuilt more than a few along the way.  But you shouldn't have to run any choke after it is warmed up.  I think Randy increases the size of the pilot jets in his kit to 42.5's which might help (those jets get plugged easily also).  Unless the main jet is way off it shouldn't be much of a player except at WOT.

Have you done or played around doing a blip test?  Simple things first have you tried to enriched your fuel air screws ?  Put a balance gauge and see how close the carbs are balanced.  Check for an air leak between the carbs and the engine, rubber boots engaged all the way around, leaking O ring at the engine block.

I would check that stuff before opening up the carbs.  If all that had no results then I would get into the carbs and clean the pilot air jets (or install new 42.5's) and have a look at the choke circuit and plungers. 

I like the adjustable needles but for now it should run as is in close to stock trim. Shims are OK also. 

Randy is the carb expert and there are others here that have forgotten more about carbs than me. They might give you some ideas also to think about.

After your bike is running and you are more than 1/4 throttle open (take some masking tape and mark the 1/4, 1/2, 3/4 throttle positions) what happens if you push the choke back in ?
George
Life isn't about having the best, but about making the best of what you have...

1990 FJ 1200

ribbert

Quote from: Dads_FJ on March 03, 2014, 09:31:08 AM
Did you pivot the sub-frame back?  The time is takes to perform that is well worth it and makes installing much much easier.

Yes
"Tell a wise man something he doesn't know and he'll thank you, tell a fool something he doesn't know and he'll abuse you"