How does your FJ sound?

[petetb154]

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

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.

[FJmonkey]

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.

[The General]

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.   

[petetb154]

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.   

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!

[FJmonkey]

What the heck is the "unipod myth re grunt punch"?

I got nothing...   

I might get a sound byte for you this weekend...

[FJ1100mjk]

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

[FJmonkey]

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

[petetb154]

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

[Flynt]

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

Sounds a little fat...

Frank

[Troyskie]

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

perhaps a tad rich, but sounded like a little follow-through 

[FJmonkey]

Never trust a fart....

[1tinindian]

Here is what my 91 FJ1200 sounded like a few years ago on the dyno.

https://www.youtube.com/watch?v=icuv7DZFS4c

[ribbert]

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

[petetb154]

Here is what my 91 FJ1200 sounded like a few years ago on the dyno.

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!

[petetb154]

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?