Who thinks their FJ runs (and sounds) perfect, smooth and sweet?
I have an 87 FJ configured as follows:
62k miles, 1mm Wiesco overbore kit, a slightly milled head and over-sized stainless valves.
A stock cam & stock cam timing (non slotted cam gears).
A V&H SS2R 4:1 exhaust.
Uni Air Filter Pods, #40 pilot jets and #115 mains. 3 turns out on air screws and recently set float height to stock. Carbs are sync'd
It's about 100 deg F in Phoenix right now at 1300 ft elevation.
Full disclosure, I haven't invested much time playing with the jetting & doing checking plug color etc.
Yet I think the bike sounds a little rough, it has a gurgle, it sounds like an old CB750 to me. Not crisp and clean. I haven't ridden the FJ for many years, so maybe my memory of how it once ran is distorted. But when I look at FJ videos on youtube, they all sound a little rough to me. Maybe modern, fuel injected, water cooled superbike perfection has set my expectations too high. Or, maybe the jetting is just a little off and I just need to spend some time tweaking it.
Check out this very short video of me pulling into the drive and tell me what you think. http://youtu.be/6DyG6pFUQfQ (http://youtu.be/6DyG6pFUQfQ)
I'd love to hear some perfect FJs run to see what they can sound like. Who's bike is running awesome?? Please post a video or sound file so that I can get motivated to tune mine more.
Sounds good to me, the FJ engine is not as sewing machine smooth as the newer water cooled FI engines we hear now. However, RPM has an FI in development and the early reports are as good as all the other RPM products. I am sure others will post up a vid or sound bite of the RPM exhaust to help compare it to your FJ.
Sounds okay from the little bit of video evidenced, but suspect the unipod myth re grunt punch, could be lurking. Worth a Dyno check given investment so far. :drinks:
Quote from: The General on July 21, 2015, 06:48:12 PM
Sounds okay from the little bit of video evidenced, but suspect the unipod myth re grunt punch, could be lurking. Worth a Dyno check given investment so far. :drinks:
What the heck is the "unipod myth re grunt punch"?
I assume that it is it a reference to the complaint that mid-range power is lost when the air box is removed? Maybe the rough sound is due to the honk of the open carbs & a mis-tuned low-mid range. I agree, it's worth a dyno run to get it perfect.
I'd still like to hear some others!
Quote from: petetb154 on July 21, 2015, 07:06:21 PM
What the heck is the "unipod myth re grunt punch"?
I got nothing... :scratch_one-s_head:
I might get a sound byte for you this weekend...
Quote from: FJmonkey on July 21, 2015, 05:57:00 PM
I am sure others will post up a vid or sound bite of the RPM exhaust to help compare it to your FJ.
Vance and Hines Exhaust with K and N Pods (http://www.shockwave-sound.com/sound-effects/fart-sounds/Long%20fart%20WAV.wav)
Quote from: FJ1100mjk on July 21, 2015, 07:11:39 PM
Quote from: FJmonkey on July 21, 2015, 05:57:00 PM
I am sure others will post up a vid or sound bite of the RPM exhaust to help compare it to your FJ.
Vance and Hines Exhaust with K and N Pods (http://www.shockwave-sound.com/sound-effects/fart-sounds/Long%20fart%20WAV.wav)
:bad:
Quote from: FJ1100mjk on July 21, 2015, 07:11:39 PM
Quote from: FJmonkey on July 21, 2015, 05:57:00 PM
I am sure others will post up a vid or sound bite of the RPM exhaust to help compare it to your FJ.
Vance and Hines Exhaust with K and N Pods (http://www.shockwave-sound.com/sound-effects/fart-sounds/Long%20fart%20WAV.wav)
:rofl:
Quote from: FJ1100mjk on July 21, 2015, 07:11:39 PM
Quote from: FJmonkey on July 21, 2015, 05:57:00 PM
I am sure others will post up a vid or sound bite of the RPM exhaust to help compare it to your FJ.
Vance and Hines Exhaust with K and N Pods (http://www.shockwave-sound.com/sound-effects/fart-sounds/Long%20fart%20WAV.wav)
Sounds a little fat... :bad:
Frank
Quote from: FJ1100mjk on July 21, 2015, 07:11:39 PM
Quote from: FJmonkey on July 21, 2015, 05:57:00 PM
I am sure others will post up a vid or sound bite of the RPM exhaust to help compare it to your FJ.
Vance and Hines Exhaust with K and N Pods (http://www.shockwave-sound.com/sound-effects/fart-sounds/Long%20fart%20WAV.wav)
:good: perhaps a tad rich, but sounded like a little follow-through :rofl2:
Never trust a fart....
Here is what my 91 FJ1200 sounded like a few years ago on the dyno.
https://www.youtube.com/watch?v=icuv7DZFS4c (https://www.youtube.com/watch?v=icuv7DZFS4c)
Quote from: petetb154 on July 21, 2015, 05:47:49 PM
Who thinks their FJ runs (and sounds) perfect, smooth and sweet?
The later rubber mounted FJ's
are turbine smooth. It is not uncommon for reviewers of late model, water cooled, injected in line 4's to still complain of buzziness at certain revs. Most annoying if that happens to be around cruising speed. The water cooling certainly makes them a lot quieter though which overlaps the senses a bit.
The later FJ's stack up well compared to new bikes in this regard and was way ahead of it's time in the day.
A well tuned FJ runs very sweetly and should stay running that way for a long time,
IF you can resist the urge to keep friggin' around with it trying to get it 100% perfect. It's chasing the last few percent of a perfect tune that involves a disproportionate amount of time and delivers negligible benefit for everyday riding, unless of course, that's your thing. One owner here even has the ground straps on his spark plugs all pointing in the same direction towards the inlet valves.
If fairly new to the forum it would be easy to form the view, just from the sheer number of posts on the subject, that they require constant fiddling to keep them running sweet, they don't. Get it running to your satisfaction then leave it alone and just ride it.
Short of something going wrong, the tune should hold for a very long time.
Carb balancing is the only thing I can think of that benefits the bike from regular checking and keeps it running sweet. I do mine about every 20,000km and even then they're not far out.
Yes, they can be smooth and with a nice exhaust, emit a lovely crisp note.
Noel
Quote from: 1tinindian on July 22, 2015, 12:25:03 AM
Here is what my 91 FJ1200 sounded like a few years ago on the dyno.
https://www.youtube.com/watch?v=icuv7DZFS4c (https://www.youtube.com/watch?v=icuv7DZFS4c)
That sounds great! Smoother, like I remember. Definitely more crisp than mine. Are you running the stock air box in this video?
Another note, it cracks me up that he scrubbed a little speed off w/ the front brake after hitting red line.. Must be a forced habit from doing this on the road!
Quote from: ribbert on July 22, 2015, 08:47:20 AM
Quote from: petetb154 on July 21, 2015, 05:47:49 PM
Who thinks their FJ runs (and sounds) perfect, smooth and sweet?
The later rubber mounted FJ's are turbine smooth. It is not uncommon for reviewers of late model, water cooled, injected in line 4's to still complain of buzziness at certain revs. Most annoying if that happens to be around cruising speed. The water cooling certainly makes them a lot quieter though which overlaps the senses a bit.
The later FJ's stack up well compared to new bikes in this regard and was way ahead of it's time in the day.
Thanks Noel, I agree, rubber mounted FJs transmit less "buzz" to the rider. I am actually referring to the uneven *sound* of my engine running. Hard to describe in text, but it just sounds like not every cylinder is running the same.. Like a few cylinders are banging while a few are popping, resulting in a rough sounding engine. Could be lots of causes for this, I'll itemize a few of my therories, from most likely to least
1. Carb syncronization - yes, they are sync'd... but this would commonly cause what I am describing
2. Jetting - perhaps all cylinders are all a little lean on pilots or air screw. Or the outside cyls might like one step richer than inside cylinders
3. The Unipods - I can hear more of the chatter of the carb slides and intake growl
4. The Pipe - Maybe the 4:1 V&H mixes exhaust pulses earlier than the 4:2:1 types, and sounds lumpy as a result
5. Leakage - maybe the compression isn't even on all cylinders. Bad valves or rings..
6. Compression Ratio mismatch - there is a chance, from some head damage caused by a broken valve that happened eons ago, that the combustion chamber on my #1 cylinder is slightly larger or smaller than the other 3 cylinders
7. Ignition - what if there is some pre-ignition going on because of ignition.. Like bad points or dwell timing might cause back in the day
Any other thoughts?
From your description of what you've done to the engine and the heat of Phoenix, you 'might' have a bit of detonation. Are you running Premium or Regular U/L (with ethanol) ?
My stock '91 runs fine on 91 octane regular UNLESS its HOT here (and we do get Phoenix temps occasionally) And, I'm able to avoid ethanol fuel in Victoria.
Also, you don't mention if you've lifted the carb slide needles. You can do this either by moving the clip or adding 0.5mm (0.020") washers under the clip if you have (US) single groove needles.
The needles will make much more difference to how your bike feels in normal street riding than either jets or pilots being changed.
When I put DualPod UNI filters on I went up to 115 mains and lifted the needles by 0.5mm
Quote from: petetb154 on July 22, 2015, 10:36:33 AM
Any other thoughts?
Yes. Put a bunch more miles on it. Go back and check your valve clearances and carb synch again.
Careful, because at some point, the Conlon mantra may need to be invoked. "Just ride the fucker."
Quote from: Arnie on July 22, 2015, 11:13:59 AM
From your description of what you've done to the engine and the heat of Phoenix, you 'might' have a bit of detonation. Are you running Premium or Regular U/L (with ethanol) ?
Regular U/L without ethanol, just 'cause it's what I had in the garage. I'll use premium on next tank and see.
Quote from: Arnie on July 22, 2015, 11:13:59 AM
Also, you don't mention if you've lifted the carb slide needles. You can do this either by moving the clip or adding 0.5mm (0.020") washers under the clip if you have (US) single groove needles.
The needles will make much more difference to how your bike feels in normal street riding than either jets or pilots being changed.
When I put DualPod UNI filters on I went up to 115 mains and lifted the needles by 0.5mm
I've got adjustable RPM needles on the middle position. Raising the needles may be the perfect fix, but I think I'll just systematically go through a complete jetting exercise, starting at the mains and working my way down to the air screws. Might use plug reading method, might rent some time on a dyno. But now that I have heard the way it is *supposed* to sound, I have the motivation to tweak it a little.
Thanks!
Quote from: petetb154 on July 22, 2015, 10:24:01 AM
Quote from: 1tinindian on July 22, 2015, 12:25:03 AM
Quote from: petetb154 on July 22, 2015, 10:24:01 AM
Quote from: 1tinindian on July 22, 2015, 12:25:03 AM
Here is what my 91 FJ1200 sounded like a few years ago on the dyno.
https://www.youtube.com/watch?v=icuv7DZFS4c (https://www.youtube.com/watch?v=icuv7DZFS4c)
That sounds great! Smoother, like I remember. Definitely more crisp than mine. Are you running the stock air box in this video?
Another note, it cracks me up that he scrubbed a little speed off w/ the front brake after hitting red line.. Must be a forced habit from doing this on the road!
I have the UNI pods on it.
I thought he was full of it, when he said, "Needs a tune up". when in reality, the carbs were a fresh rebuild by Randy at RPM, the valves were adjusted, new plugs, and the pods installed.
If anything, it needed the coil relay mod done to help with high rpm performance.
Trust me, it runs very nice and I'm not always making adjustments, I just ride the damn thing!
Quote from: petetb154 on July 22, 2015, 12:16:36 PM
I've got adjustable RPM needles on the middle position. Raising the needles may be the perfect fix, but I think I'll just systematically go through a complete jetting exercise, starting at the mains and working my way down to the air screws. Might use plug reading method, might rent some time on a dyno. But now that I have heard the way it is *supposed* to sound, I have the motivation to tweak it a little.
Hey Brian, I also live is the desert (just west of you) and I can tell you that in hot weather, at close to sea level, my bikes run much better with premium gas.
Before carb tuning: Make sure your valves are adjusted. Make sure your floats are set. Make sure your carbs are synch'ed. Fresh plugs.
You are on the right tract on the order your carb tuning:
First: The main jets. The correct sizes for WFO engine performance.
Second: the needle position. You already have adjustable needles so go ahead and try raising the needle position one full notch first. If this makes things better, then you can always go back and try fine tuning with the 1/2 step shims that Arnie suggests. The shims are equal to 1/2 a notch on the adjustable needles. Remember that your bike is running on the needles the majority of the time. Having the needles raised too much will waste gas, but it is still safer than running too lean, especially in our hot climates.
Third: Select your pilot jets. Start with #40 pilots and go up from there.
Fourth: Set your air/fuel idle jet screws on a warm bike. Use the blip test. Start your screws 2.5 turns out and go from there.
Fifth: Adjust your idle speed. 1,000 rpm works well for me.
Do your carb tuning following the above sequence. If not, you will drive yourself crazy. Trust me.
.
Quote from: 1tinindian on July 22, 2015, 01:09:21 PM
I thought he was full of it, when he said, "Needs a tune up". when in reality, the carbs were a fresh rebuild by Randy at RPM, the valves were adjusted, new plugs, and the pods installed.
I'm going to go out on a limb and guess that he sells tune-ups. He's FOS! You bike sounds good and makes very respectable RWHP. Congrats.
The coil mod is something I hadn't thought of, that could impact how smooth the bike runs.. That's something easy to test.
Thanks.
Quote from: Pat Conlon on July 22, 2015, 01:20:25 PM
Hey Brian, I also live is the desert (just west of you) and I can tell you that in hot weather, at close to sea level, my bikes run much better with premium gas.
Very cool. We just moved here from Nebraska a year ago and the summer heat is.. well... something! :diablo: In fact, I might have to buy an oil cooler. :-) I haven't explored the best street bike roads in the area yet, but I do know that this place is a dirt bike & Jeeping Mecca!
Quote from: Pat Conlon on July 22, 2015, 01:20:25 PM
You are on the right tract on the order your carb tuning:
Yup, top to bottom is the only way to go. It seems like a lot more work at first, but as they say, there is always time to do it right the second time. I just needed this conversation to get me motivated to do the work.