Wide Open Throttle question

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Steve in Phx

Well-known member
Joined
Oct 8, 2009
Messages
164
Reaction score
26
Location
PHX
Something I've noticed out on the open road. This is hard to articulate but hopefully someone will understand.

I am not an aggressive rider and never hit redline so this isn't a big concern, just curious more than anything.

If I slowly open the throttle to wide open, the bike pulls strong until I hit about 80% throttle. When I open that last 20% it feels like I'm losing torque. If I back off the throttle a bit, it pulls stronger again. Don't get me wrong, it still pulls like crazy, but not as strong during that last 20% of throttle opening. So I get more power if I don't open the throttle all the way. Not lugging it, but let's say this is consistent between 4000-8500rpm.

If this was my dirt bike, I would guess new jetting is needed. Is this something the Barbarian Mod would help with?

I bought the bike with 8K miles on it and it's at 26K now. The previous owner didn't modify anything. When I purchased it, I unwound one rotation on the spring and did the G2 throttle tamer mod. Nothing else has been changed.

Thoughts?

 
Check the TPS if this read from about 15 throttle closed to 100+/- at wide open.

Also as SLK50 wrote above,check the filter if it is dirty and also check the area around there if a mice has build his home..
smile.png


 
IIRC, the Barbarian jumper mod has very little effect at anything above an idle.

Pretty sure it will have no effect at anything close to WOT.

 
AE bike might have something to do with that. Never rode one.
The Gen 2 YCC-S does nothing to engine power unless you do a gear change with the throttle wide open causing the engine to rev too high, then the ignition is retarded to reduce power whilst it slips the clutch trying to match engine and gearbox speeds. Nothing to do with simple accelerating.

 
Last edited by a moderator:
I have an 07 as well, and don't do much wide open throttle riding, but the next time I go out I will try to run it like this a couple of times to see if mine acts like that. It is hard to do as in the lower gears you get to redline so fast it would be hard to evaluate, and in the higher gears you are well over 100 before you know it. LOL

Are you going to check the valve adjustment soon? I wonder if you might have a tight valve or two??

 
I'm going to see if i notice this the next time I'm out on my 2007 with a G2, and I can find a road long and straight enough. But until then, take off those throttle bodies and install a set of constant velocity carbs
winksmiley02.gif
?

 
The torque curve doesn't peak until closer to 7500. I've seen stuff that claims it drops off anywhere between 6800 and 7900. However, my '07 pulls like a train all the way to red line. Obviously in 5th gear that's not quite true, but from first to 4th, I don't feel any drop.

 
The torque curve doesn't peak until closer to 7500. I've seen stuff that claims it drops off anywhere between 6800 and 7900. However, my '07 pulls like a train all the way to red line. Obviously in 5th gear that's not quite true, but from first to 4th, I don't feel any drop.
Yep, mine too. I had it out today, gps max speed said 137 (speedo about 145). Had no difficulty getting there even in 5th. This was a roll-on from 60-ish in 5th gear.

 
I wonder if I'm just not revving it high enough?

I performed the first valve gap check yesterday and all of them were perfect at 27K miles.

 
I guess that's possible. I tend to stay in the 3000- 5000 range for the majority of my riding but will rev 'er up once in a while.

You asked in your OP if the Barbarian mod might help. Now, I don't know about the AE side of things, and lots of non-'07 folks will prolly gnash teeth and wring hands, but I feel the Barbarian mod helped my '07 a lot. Remember, the '07 was (still is!) a bass turd in many ways. IIRC I bumped up about 7 pts on each one and it made a big difference with "smoothness" throughout my "normal" speed range. I say- give it a shot. It's an easy adjustment (move a wire) and an easier "put back". I logged in my owners manual what I started with and incrementally tried.

Another recommendation- from this point on completely disregard anything about the Barbarian mod said by anyone who does not now or has not in the past owned an '07. Sure it's an FJR but sometimes it's not.

 
Rev it higher. If you're in 4th gear at 75 and open the throttle all the way it reduces intake velocity. Air moving through a larger opening than needed. Down shift.

What is the true redline? Tach shows 9500 but mine revs higher. Soft . 10,500 shuts off spark or fuel. ?????

 
She'll definitely pull hard to the redline. If you're running hard through twisties, you should ALWAYS be above 5k; engine braking means no need to touch the levers.

And mech 1 twa, mine's hit the rev limiter a half-dozen times, but I've never looked down to see where.

 
Last edited by a moderator:
She'll definitely pull hard to the redline. If you're running hard through twisties, you should ALWAYS be above 5k; engine braking means no need to touch the levers.
And mech 1 twa, mine's hit the rev limiter a half-dozen times, but I've never looked down to see where.
Oh you must have a 6 speed then.
smile.png
WE need more emojis to express are feelings.

 
1. Air Filter

2. My bet is you still have the stock PAIR system installed. One or more of the reed valves is carboned open or carboned stuck shut. Remove all that PAIR crap, cap it with a set of the PAIR plates made by somebody on here. Go hug a tree and apologize for your renewed environmental impact and I dare you to look down when redlined in 5th. Actually I take that back. Just smile and keep going.

 
Top