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FairWeatherFellow

4th Gen Dyno charts/results

So I'm curious, what kind of power is your VFR 750 making? Also what modifications have you done to get there? I have a Two Brothers full system, factory style paper filter, and someone cut a hole in the air box for whatever that's worth. No idea if it's been jetted, but the carbs looked untouched with factory Philips head screws.

 

large.IMG_20160713_175752477.jpg.e3f0eb951837c8043027adcb8e4f4168.jpglarge.IMG_20160620_211252412.jpg.ed78742f636c662137cdb84058188c58.jpg

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2 hours ago, slowbird said:

Yup. OE style filter. Stock plugs. Stock unmodified airbox.

 

Removal of the PAIR or AIS will have no effect on the bikes performance, but it will make the Dyno read the A/F ratios more efficiently.

I noticed ZERO difference when I removed the PAIR system from my old 4th gen.

That's good to know, I appreciate the info! Nice to know a stock baseline for power. Are you near sea level? I think I'll wind up checking on the PAIR or AIS and see if it really is removed. 

 

1 hour ago, coupedupsubie said:

I believe my PAIR(AIS) was malfunctioning which can effect the running of the bike in my opinion, it became slightly more responsive but not a lot. The original reason I deleted it was to get proper A/F ratio readings.

 

 

I thought I saw an older round metal two bros can in one of your pictures.

Makes sense, considering its function it could affects things if it's not working right. No sir, carbon fiber 18" two Bros that's now 11"large.IMG_20170211_120346347.jpg.6500c2edb389137310ec89db7a9ae829.jpg

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Looking at that AFR, you are really rich. Maybe you need more air box mods (high flow filter and snorkel removal?) or maybe you need to work on the jetting, but your AFR is very rich. The dashed line is 13.2 which is optimal, and the solid line is where you are at right now 11-12, well below optimal.

 

The powerband itself looks great, but I would expect more peak power with that Two Brothers Full Exhaust, though I am not sure what 4th gens average, which could be lower.

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106, but dynos differ as do atmospheric and temperature conditions.

 

post-5787-0-83690300-1467705930.jpg.b9e35c8c24cb172bb34e996eccfcd8ac.jpg

 

I would plug that hole...

 

 

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3 hours ago, CandyRedRC46 said:

Looking at that AFR, you are really rich. Maybe you need more air box mods (high flow filter and snorkel removal?) or maybe you need to work on the jetting, but your AFR is very rich. The dashed line is 13.2 which is optimal, and the solid line is where you are at right now 11-12, well below optimal.

 

The powerband itself looks great, but I would expect more peak power with that Two Brothers Full Exhaust, though I am not sure what 4th gens average, which could be lower.

I have a UMI aftermarket filter that I pulled out of the bike when I first got it. It was over oiled big time. I put in factory style because I wanted a good baseline for my Dyno. I'm going to throw it back in and try snorkel delete and plugging the hole too and just see what happens.

 

Average I've seen is low-mid 90's so I'm at a OK place. Just wanted to see what people are getting to see if it's worth the $$ for more ponies.

3 hours ago, Dutchy said:

106, but dynos differ as do atmospheric and temperature conditions.

 

post-5787-0-83690300-1467705930.jpg.b9e35c8c24cb172bb34e996eccfcd8ac.jpg

 

I would plug that hole...

 

 

106 is pretty high! What have you done to the bike? I'd be extremely pleased if I could get 13 more ponies out of her...

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CRRC46 is right-that is very rich. Seeings' how you're at sea level (or close compared to me) I'll bet somebody has been in the carbs. Mine still have the Phillips/8mm hex screws in them and I had to go in and put the jetting back to stock to get it to run right. I'm running stock style filter, high mount Staintune w/big spud and (Dutchy's right-plug the hole) NO airbox mods. On the 4th Gens the snorkel is important for cutting the turbulance of the intake air. I tried removing it and it really hurt my low and mid-range response. I've never dynoed mine but it'll pull like a freight train to redline and I average 45 mpg. (at 5500 ft. elev.) Also check and see if anybody raised the needles. I know dyno time ain't cheap but IF YOU CAN just change one thing at time-so you know where to go back to if it doesn't work. 

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Awe back in the day my 4th gen was dialed in at 98Hp with a Stainetune with a KN at the time like 10 years ago, had it to get into the Jets,  but Mr. Valasco advised there's really only one trusted kit he would use, ;)  an HRC one. Might as well be looking for gold.  Since it was running real good,  we left things alone for the better.    We can talk about  about this tomorrow too.

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Years ago, I simply had the Akrapovic fitted (with db-killer) and no re-jetting.

For redslut, I applied the "treat 'm mean, keep 'm keen" scenario; she had to work hard....

 

With some money to blow (and my 5k miles trip coming up) I took her to a dyno shop.

We agreed on a K&N (tbh, the paper filters are ok too...), and some work on the carbs (different springs, "307" needles whatever that means and mj/24 jets).

The one thing that stood out for me was the improved fuel consumption, some 10% better mileage

 

The new needles were the adjustable ones

post-5787-0-10958700-1467279379.jpg

 

 

Did she "need" all this work?  No, be it 95, 98, 100 or 106, the RC36 is powerful enough as is...

 

 

borrow a Carbtune (I bought one years ago) to sync your carbs and be done with it if you donot have cash to blow.

The shop checked sync with their jazzy tool and they were pretty close...

post-5787-0-67207500-1467279379.jpg

 

 

 

 

 

post-5787-0-59888200-1467279366.jpg

 

 

 

 

 

 

 

1st and foremost, invest in PROTECTIVE GEAR for yourself; one never knows when you need it to save your bacon...

 

 

IMAG5004.thumb.jpg.19144469a1412c1b8ed490ba7dc2652d.jpg

 

 

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Wow.. and Yikes,  this brings back  a sad day. ^  yes been there. smh. it only took 2 months before i was up and around again,  but at least I could. 

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Yes safety is key! I have full gear and a chest/back protector I wear under my jacket as well. I went through a field at 45 last year and walked away so I'm always sure to gear up for the worst!

 

Well that's good facts there. I going to run an AM air filter to see if I can't lean out the AF mixture just a little bit. After flipping through a few threads I've decided to go with the Piper cross filter, and also close up the hole in the air box. I'll Dyno it after and post the results. Could potentially get a little carb work done as well, for it could have been jetted for the UNI filter that was in it when I got it. I'll check to see if the carbs are in sinc too

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May I suggest you drop in and see Mike Valsco at Brothers Power sport  when all is tidy upped,  he likes them V4s.

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Yes I will definitely contact him. I usually go to Nels at 2 Wheel Dynoworks in Redmond. He did wonders for my Aprilia, but that was EFI. Would be nice to go to someone who's about the bike!

 

Also I'm in the middle of contemplating shortening my Two Bros can... I want more DB's and I like the look of a shorter can. Plus why spend $300 on a different one. Maybe I'm not seeing the downside at all, slip ons have such a minimal effect on Dyno numbers. Though everybody swears by one thing or another, back pressure, and air flow..

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My old 4th gen put down 90 rwhp in stock trim.

 

I have a thread on here but the dyno pic isn't available anymore (thanks Imageshack) though the link for the Youtube vid is.

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9 hours ago, slowbird said:

My old 4th gen put down 90 rwhp in stock trim.

 

I have a thread on here but the dyno pic isn't available anymore (thanks Imageshack) though the link for the Youtube vid is.

Interesting, OE style filter, and OE exhaust as well? 

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Shortening the Two Bros can just a couple inches will make it louder. If your can is getting pitted like mine you can get 4" pipe/tube in the right size. I will double check the exact thickness tomorrow.

 

As for power I will be putting mine on the dyno this spring if I can. Mine has a TBR left exit, AIS delete(doubt yours has AIS with those AFR readings), stock filter, rejetted years ago. 

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3 hours ago, coupedupsubie said:

Shortening the Two Bros can just a couple inches will make it louder. If your can is getting pitted like mine you can get 4" pipe/tube in the right size. I will double check the exact thickness tomorrow.

 

As for power I will be putting mine on the dyno this spring if I can. Mine has a TBR left exit, AIS delete(doubt yours has AIS with those AFR readings), stock filter, rejetted years ago. 

What do you mean by getting pitted? And I'm assuming your talking about just straight pipe yes? Open exhaust sounds realll nice, but I'm not sure I could do open all the time. I wound up cutting the pipe from 18" to 11". Will repack and rivet tomorrow. Stoked to hear how it sounds.

 

When you get that Dynoworks read out be sure to post it! Also I'm not familiar with AIS.

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9 hours ago, FairWeatherFellow said:

What do you mean by getting pitted? And I'm assuming your talking about just straight pipe yes? Open exhaust sounds realll nice, but I'm not sure I could do open all the time. I wound up cutting the pipe from 18" to 11". Will repack and rivet tomorrow. Stoked to hear how it sounds.

 

When you get that Dynoworks read out be sure to post it! Also I'm not familiar with AIS.

Yes, just straight pipe. The original shell of mine was aluminum, it got pitted over the 15+ years it was on the bike. I replaced it with a section of 304SS painted black. 

 

AIS(Air Injection System) was made to appease emissions people. It creates a lean environment just after the exhaust valve. Not all bikes got it back in the 90s.

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Oh OK I see. Yeah mine is a two Bros carbon fiber, which has been fairly weathered by UV. I tried to polish it up but a lot of the resin is gone. I'm not too worried about it though, if the shortened version has the desired sound I may clear coat it. Straight pipe is fun but I need at least a little sound deadening.

 

I gotcha, is it common to delete that on these bike? Damn emissions always ruining the fun.

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On 2017-02-20 at 6:28 PM, FairWeatherFellow said:

Interesting, OE style filter, and OE exhaust as well? 

Yup. OE style filter. Stock plugs. Stock unmodified airbox.

 

Removal of the PAIR or AIS will have no effect on the bikes performance, but it will make the Dyno read the A/F ratios more efficiently.

I noticed ZERO difference when I removed the PAIR system from my old 4th gen.

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I believe my PAIR(AIS) was malfunctioning which can effect the running of the bike in my opinion, it became slightly more responsive but not a lot. The original reason I deleted it was to get proper A/F ratio readings.

 

On 2/21/2017 at 2:08 PM, FairWeatherFellow said:

Oh OK I see. Yeah mine is a two Bros carbon fiber, which has been fairly weathered by UV. I tried to polish it up but a lot of the resin is gone. I'm not too worried about it though, if the shortened version has the desired sound I may clear coat it. Straight pipe is fun but I need at least a little sound deadening.

 

I gotcha, is it common to delete that on these bike? Damn emissions always ruining the fun.

 

I thought I saw an older round metal two bros can in one of your pictures.

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I made 89.2rwhp on my 97 FV - I was pretty pleased with that.

 

That was after I'd put 92,000 miles on it.... and then left it in a lock-up for 8yrs.... and just got it going again long enough to get it to the dyno.

 

It had lost nearly 1hp.

 

Honda. They know how to build quality kit...

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27 minutes ago, Ghostrider said:

I made 89.2rwhp on my 97 FV - I was pretty pleased with that.

 

That was after I'd put 92,000 miles on it.... and then left it in a lock-up for 8yrs.... and just got it going again long enough to get it to the dyno.

 

It had lost nearly 1hp.

 

Honda. They know how to build quality kit...

Yes they absolutely do! You do any carb work before you got it dyno'd? Not sure how long my bike sat, but it spent a good long part of its life sitting in the sun.

 

I just replaced my stock style filter with a Piper cross filter and plugged my air box hole. Interested to see how much of a difference it will actually make..

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8 minutes ago, FairWeatherFellow said:

Yes they absolutely do! You do any carb work before you got it dyno'd? Not sure how long my bike sat, but it spent a good long part of its life sitting in the sun.

 

I just replaced my stock style filter with a Piper cross filter and plugged my air box hole. Interested to see how much of a difference it will actually make..

Nope. I'd taken it to the dyno as I had a horrible flat spot just as the main jet comes on ISTR @ 5,000 revs. Other than a proper clean up and having the carb rubbers sealing properly, the only mod was a K&N filter...

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1 hour ago, Ghostrider said:

Nope. I'd taken it to the dyno as I had a horrible flat spot just as the main jet comes on ISTR @ 5,000 revs. Other than a proper clean up and having the carb rubbers sealing properly, the only mod was a K&N filter...

 Interesting, what was your A/F mixture like after the K&N?

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Couldn't tell you from the top of my head - it was about 4yrs ago - but I'll have a little hunt around for the dyno print...

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So I took her to the dyno again today. I patch up the air box mod, installed a Piper cross air filter, patched up my TBR system, and put a non restrictive mid pipe on. I was hoping that it would potentially lean me out just a little. But in actuality it just made me richer than before. New dyno number says 88 and old is 93 but I didn't actually make less power, software update for the dyno is 5% more accurate and less generous haha. Nels told me I should go down 5 on the main jets...Sooo what size is the main jet? Also how do I check the size of the jet that's in there if it isn't factory... Thanks ahead of time!large.IMG_20170408_163324561.jpg.507ce88c5e69c9de8752011dcefe6ac2.jpgVID_20170408_101442803.mp4

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