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PCV Flat spot, suggestions needed please.

31K views 221 replies 44 participants last post by  chrismpero 
#1 ·
Installed a PCV. Installation went smoothly. I have my reservations regarding the TPS crimper, but owell. The very first ride I took after installing the PCV, I noticed a flat spot. I have pinpointed, I believe, the area. It appears to be at ~ 4800 to 5200 RPM. Never had an issue prior to the PCV being installed. The flat spot rears its ugly head in gear 2, 3, 4 at least. If you goose the throttle before 4800, you can roll right through the flat spot and never hit it. If you goose it in that range though = significant stutter. This is turning out to be a problem, as when in traffic, bursting inbetween cars, etc., it turns out that 4800 - 5200 is where I usually am. Is this issue merely a matter of going in and smoothing out the map I installed, or is there another more serious issue? The map I use was meant for Yoshi slipons and aftermarket/stock air filter. Thanks in advance for any help!
 
#4 ·
I think this is an issue that others are seeing. I actually have akra slip on and I loaded the correct map, but i also have that exact spot where i am definitely missing power..it is very noticable. i see it also when i am on the highway..if i decided to barely turn the throttle, i feel like theirs absolutely no gas being pumped.
 
#6 ·
my friend also told me about this when he tries to hammer on the throttle. Gotta love 1st generation products.
 
#7 ·
Yes! this is the same problem I'm having, very frustrating I might add. It's okay when I'm WOT, but while cruising with the throttle just cracked, 4-5K is very boggy, either like it's getting way too much gas or not enough, you can actually watch the RPM's jump a little, but as soon as you hit 5.2K or so, it smooths right out and runs great. Again, with WOT, this is not noticeable. What gives?!

PS - I have the latest firmware with the exact map matching my setup, Two Brothers Carbon Slipons and stock air filter.
 
#8 ·
I think I've decided tonight, after a bottle of wine, that I'm going to pull off the PCV until they either square away the issues or I move back to the mainland and can find a really good tuner. That little issue just really annoys me and DynoJet has to know about this and is kind of ignoring it. DynoJetResearch hangs around some other posts but he still hasn't given any clear resolutions after months of people pointing out this issue. Oh well, I wonder if that Bazzaz is having the same issues?
 
#10 ·
Do you have the auto tune installed? I've been reading some other threads and they've been able to fix it with some tricks with the trim tables. I think when most people even have these tuned, they're just looking to set the tables according to WOT, you probably have to have the tuner specifically look for 10-15% throttle and 4-5K RPM to adjust as necessary. I dunno, it's off and it's staying off until there's a resolution.
 
#12 ·
I see how you could think it was a misfire. I think it's loading up with fuel causing an extremely rich condition or something. Some guys are saying it's a YCC thing with the throttle body lengths changing and the system trying to find an economical setting for emissions and whatever while cruising, the PCV is trying to dump fuel for performance bases? I'm not really sure, just fed up with it. I hate to keep the bike rev'd all the time over 5k, so I just removed the system. I guess I could have just put a "zero tune" on it and called it good, but I like to elminate the PCV system out of the loop competely. Need a good tuner or the smog block offs and the auto tune system.
 
#13 ·
yeah, since i was having this problem, i took the pcv off the bike because it was running really rich..my damn jacket smells like gas now!! the whole tail end was smoked out..Dont know what happenned but NOW, the bike runs very poorly at 4-5000rpm without the pcv..so i re-installed the pcv with the newest firmware and re loaded the map. Now the bike runs amazing, BUT once again, VERY rich...now im going for a good tune this saturday with a tech. that worked with yamaha. ive seen him add power where i didnt think was possible to add more. im pretty excited for that.

But, what gets me wondering now is why the bike ran soo poorly without the pcv? i had no power and to make things worst I decided to wot on 2nd gear and the throttle completely shut down! the bike was on, but no no throttle response...it all started when i washed the bike 2 weeks ago..i didnt think water could screw up your settings for soo long..well i hope its the water..then it should comeback to normal..
 
#14 ·
wondering if it has something to do with the throttle position sensor, what wire did you splice into for the PCV and how did you do it? You might have some gotten some water in there and grounded it to something else, maybe not but it's a possibility. I put the PCV back on and put a zero tune on it, ran fine with the zero tune, really no bogging that is noticeable, right when the smog system is pumping that fresh air into the exhaust that seems like when it's bogging a little so when I get my smog block offs I'm gonna see if that makes a difference. I put the Two Brothers map back on it and calibrated the TPS closed side and just put in 4.12V at the WOT, this should have gotten it close enough to run good, then it ran great for about an hour, then started to act up again. Gonna see if the smog stuff is what's giving the issues, we'll see.
 
#18 ·
yeah, im also thinking water got in the tps! but its been 2 weeks now and still running very rich! I figured ok, water may not evaporate that fast, specially if its stuck within a wire but still 2 weeks!!! this is why im going for a good tune this week end...theyre saying its supose to be like 65 degrees on sat with dry temps. so it should be good for dyno readings..

btw, i did tap into the white wire of the tps harness...i believe thats the correct one.
 
#19 ·
Kismet; I'm thinking the Autotune could fix the mid range, 2-5% throttle opening hesitations, are you doubtful? According to that StarVmax website write up about the Autotune, he set his target A/F ratios in the 2-5% throttle openings all to zero until 5K RPM at 5% throttle opening, due to the system trying to adjust on decel. Also according to DynoJetResearch on another thread he said that most other systems zero those out to because of driveability issues.
 
#21 · (Edited)
Kismet; I'm thinking the Autotune could fix the mid range, 2-5% throttle opening hesitations, are you doubtful? According to that StarVmax website write up about the Autotune, he set his target A/F ratios in the 2-5% throttle openings all to zero until 5K RPM at 5% throttle opening, due to the system trying to adjust on decel. Also according to DynoJetResearch on another thread he said that most other systems zero those out to because of driveability issues.
I have messed with the autotune so much now I am getting pissed with it (it was me who found the AT blog on the Starvmax site) I have tried allsorts, I only bought the AT to make the lower end of things 'perfect', I have done all the sensor tests etc etc.

I think the AT will try and remove decelleration fuel as well as fuel added by blipping for downchanges and any sudden r/hand movements that will cause the std ecu to add more fuel for smooth running

I set the AF target to as low as 12.5 in the 2 and 5% column and opened the parameters up to 10% (i had been running less) the AT adjusts the fuelling to what I believe is correct Af you have aimed for.

What it does not allow for is the difference between constant rpm and acceleration fuelling (transient fueling--fuel added by the std ecu when accelerating--like a carb accelerator pump) which I think the AT then tries to remove.

I have tried riding the bike like fxstein says-constant throttle-de clutch it etc etc, and the when looking at the trims there is usually a massive -ve reading somewhere in the colums, probably from a slight twitch of the r/hand or a forgoten downchange 'blip'

I really am coming to the conclusion that the AT is a good effort by DJ but I feel it is no where near the 'plug and play' that people are falling for, just search other forums, it's not just R1's having the same issues
 
#24 · (Edited)
We just bought an 09 R1 so we can look into this problem. Will post any info as soon as possible.

We did see that if you roll on the throttle into the upper RPM the throttle does stay at around 5% and slowly comes down. This is not an issue however as the bike also shuts the injectors off down to 5500rpm so the AFR is so lean that the Auto tune ignores the data anyways.
 
#26 · (Edited)
We just bought an 09 R1 so we can look into this problem. Will post any info as soon as possible.

We did see that if you roll on the throttle into the upper RPM the throttle does stay at around 5% and slowly comes down. This is not an issue however as the bike also shuts the injectors off down to 5500rpm so the AFR is so lean that the Auto tune ignores the data anyways.
Thanks for that, i am waiting for Akrapovic to send me the db inserts from the full race system (the outlet goes from 28 to 36mm (I think, large increase anyway, running db less where I live is a no no)

I was then intending to take the bike to the lad who usually does my 'custom map' it will be interesting to see what he comes up with in the 2, 5 and 10% columns. My reason for the buying the AT was so I can swap/remove the db inserts/refit the std system etc and the AT will take care of it

I find the real 'test' for the AT is to find a quite road and leave the bike in 1st, my fixed map has 4 and 5% added in the 2 and 5% columns and runs real nice.

With the AT set to work in these columns it will just take more and more fuel out until the bike won't even keep the same rpm with me holding the throttle and bar weight for throttle stability, usually at around the 5-6000rpm mark, I then keep the throttle locked, pull the clutch to see what rpm it goes to which I can then repeat at home conneted to the laptop to see the throttle % opening.

One thing I have noticed when messing about is the problem in these small % throttle openings is worse the slower I accelerate, as I mentioned previously it is better if I set the target A/F lower, I have been to 12.5/1.

I did ask the question a while back ''how clever is the std ecu'' (before I fitted the PCV/AT) I asked this because if I swapped akra to std exhaust the bike would run snatchy at small throttle openings for 20 minutes or so, as if the o2 sensor was out of its expected range and the ecu was shiffting the whole fuel map to suit, I do wonder if the ecu is still messing about at small % openings, it does seem that the area where people are having the issues are where the ecu should be running closed loop?

You did say that it's possible to run the std lambda in these closed loop map areas, is it also possible to 'offset' the std settings with some sort of in line 'box' to richen things up from the 14.7 AF it would then aim for?
 
#25 ·
DynojetResearch; I'm glad you're finally looking into this on the PCV and Autotunes, I've been playing with the trim tables with your Two Brothers map (US) and right now I'm up to 9's in the 2%, 4-5K RPM range and it's still surging/sputtering, but it really only seems like on the decel when you've got the throttle cracked to begin cruising after an acceleration. I've used the zero map and there's no sign of this reaction from the bike. I've tried the Yoshimura map and it seems pretty good as well but if you look at the map, there is very mild adjustments in the tables. Compared to the Two Brothers Map the differences from the 2-5% in the 4-5K RPM range are much different, the Two Brothers making VERY large changes as large as 0-15 between 2-5% TPS openings. I thought this may be the issue so I was raising the 2% to make it an easier transition. Seems to have worked a little but still has the issue.

Looking forward to hearing what you guys come up with!

~Brandon (US Marines, Hawaii)
 
#28 ·
I want to smash my Auto-Tune with a sledge hammer. I've put probably 500 miles on the R1 just trying to work this thing out. Does not matter what the **** I do. The numbers are crap and wonky. 4500 rpm with 10% throttle opening will be -80 then 5000 with 10% throttle will be +67. Coming off the throttle quickly results in some seriously huge backfires and flames shooting out. I believe I'm getting around 1-2 mpg with the auto tune. I gotta fill up with gas like every 30 miles. Auto-Tune is coming off tonight. P.O.S. I've upgraded the firmware. Tried a few hundred maps, tried tips and tricks on some other forums.... nothing. It just doesn't work with the throttle by wire. Too many electronics ****ing with the fueling all at once = bad things happening. I'm going to put it on the Honda with good old throttle cable and see how it works with that.
 
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