Tire burn out with Cat Bypass & Big City Thunder Baffle

[Wildrice]

I agree--a burnout if good for the soul. However--since I installed the Cat Bypass & Big City Thunder Baffle from Lamont--I have not been able to burn out anymore--2015 F3's appears to have more acceleration after 3000 rpm. Sending my ECU in to Monster Fuel in hopes of correcting the lack of off the line torque. It just may be taking off faster without the burnout but I miss it.
Darrell
PS: I installed the Big City Thunder Baffles approx 1"+ closer to the header area(than shown in directions) but I doubt that should make a difference on back pressure torque.

[Chupaca]

Do let us know how things go when you get your ECU back... I have a manual on the last of the 106hp twins and burn out whenever....do have the Yoshimura R77....and a few other things....

[Wildrice]

Do let us know how things go when you get your ECU back... I have a manual on the last of the 106hp twins and burn out whenever....do have the Yoshimura R77....and a few other things....

Will do--doing some traveling vacation, HS Reunion, elder family health issues, etc. Probably mid to late Sept to get things back ,tested. I'm looking forward to it. I'll keep you posted.
Darrell

[2dogs]

I don't do the burn-outs, however my butt dino seems to be telling me I too don't have the "off the line torque" I used to have. I have a 1330 with the Lamont cat-by-pass with the BCT baffle that's mounted at the muffler end of the by-pass pipe. I could be wrong, but I was under the impression that the by-pass with the baffle would increase lower end torque and w/o the baffle, it would increase high end torque. My MPG really hasn't changed much if at all. I get a little more growl sound, which I like, from the modification but the engine noise from the 1330 drowns most of that out.

[BLUEKNIGHT911]

I agree--a burnout if good for the soul. However--since I installed the Cat Bypass & Big City Thunder Baffle from Lamont--I have not been able to burn out anymore--2015 F3's appears to have more acceleration after 2000 rpm. Sending my ECU in to Monster Fuel in hopes of correcting the lack of off the line torque. It just may be taking off faster without the burnout but I miss it.
Darrell
PS: I installed the Big City Thunder Baffles approx 1"+ closer to the header area(than shown in directions) but I doubt that should make a difference on back pressure torque.

Are you comparing this with the same Brand of tires ???? ....it could make a difference .... Also if your PSI is considerably lower you will a LOT more traction...... ........................good luck Mike

[Bob Denman]

Reducing the back-pressure is usually a pretty good way to KILL the bottom-end power of the bike... Try adding some of it back in to the system, and see if you notice any improvement.

[millerrdjr]

People always confuse increasing velocity with adding back pressure. Any increase in back pressure is a negative, because it increases exhaust pushing back and staying in the cylinder. You can't add back pressure to stop reversion, it increases it. The mechanism that stops reversion is unrestricted high velocity that pulls a vacuum on the exhaust port.

[fatboy]

i have the same set up and love the sound burn outs are no problem

[Wildrice]

Reducing the back-pressure is usually a pretty good way to KILL the bottom-end power of the bike... Try adding some of it back in to the system, and see if you notice any improvement.

Is your thumb available? Other than that I'm out of ideas that won't effect normal & higher rpm power. Bob--how fast can you run? I don't want a 10 mph spyder

[Wildrice]

People always confuse increasing velocity with adding back pressure. Any increase in back pressure is a negative, because it increases exhaust pushing back and staying in the cylinder. You can't add back pressure to stop reversion, it increases it. The mechanism that stops reversion is unrestricted high velocity that pulls a vacuum on the exhaust port.

Correct on high rpm--but I'm concerned with off the line SE6 torque. Mike--tires are the same my rear tire is at 28 psi.

[Bob Denman]

Bob--how fast can you run?

I don't run... I only "walk briskly" now!

[Yazz]

I had a cat-delete done and kept the OEM pipe on. It ran like crap. That was strange because people say it runs better after the delete. Had a baffle put in and it was a little better, but not great.

Found out what the problem was.... When working on a Spyder, you have to work with the onboard computers too.

I took the baffle out, reinstalled the OEM pipe and let it idle for 7-10 minutes to let the computer learn the new configuration of the exhaust system.

The F3 is a whole new ride. Woo Hoo!

[BLUEKNIGHT911]

Correct on high rpm--but I'm concerned with off the line SE6 torque. Mike--tires are the same my rear tire is at 28 psi.

... sorry but I haven't memorized what brand of tires you are running ..... if Kenda's the psi is fine .....if car tires - any car tires you are 10 psi over ( IMHO ) and should be able to spin the crap out the tires also imho ...... Mike

[Dennis in Lodi]

Based on our testing, any exhaust change requires about 200 miles for the ECU to finalize the mapping options. There are 72 different fuel mapping tables and each of those has variations. In order for the ECU to get it together it has to average out AFR readings.
You have to give credit where credit is due, in all the testing for the Monster Fuel Flash, the stock exhaust was the best performer with or without the flash up to 5,000 rpm.
The second best test results for low end were with the cat in place and a free flow exhaust.
HOWEVER, Monster Fuel addressed all those exhaust combinations and put a really big hit there for off the line. In fact, if you have an F3 with an 89 tooth sprocket, you can go sideways in 2nd gear with the stock Kenda. Monster Fuel has spent hundreds of hours and I have over 5,000 miles of testing. The new flash is programmed to deal with ALL exhaust configurations. Always allow 200 miles before expecting full results.
I'm starting stage 2 testing with a brand new 2016 F3 Limited. It has the 89 tooth sprocket, same as the F3 line up. Stage 2 will raise speed restrictions that are in the stock ECU starting at 92 mph in the RT and 105 mph in the F3 to 120 mph for both Spyders. This means an F3 will pull FULL POWER to 120 mph before the butterflies begin to close instead of 105 mph.
For me and my new 2016 F3 limited, I'm sticking with the stock exhaust, 8,600 rev limit, stage two 120 mph speed. Test are showing I''ll only be about two bike lengths behind any free flow exhaust combination up to 100 mph, then I'll drop of a little bit.
Any purchase of a stage one mapping always qualifies for Free upgrades for the cost of shipping.
As far as tire spinning take a look at the video of my RT laying down 50' of rubber. The front end is floating when it hooks up and in two of the hole shots the nanny doesn't kick in.
Also pay close attention at the end of the video where I say 5,000 to 7,000 roll on testing. This is where all the money begins for performance. For the RT this the premium rpm range for passing and trailer pulling. For the F3 5,000 rpm is where you get your wings.
https://monsterfuelinjection.com/spyder/

I agree--a burnout if good for the soul. However--since I installed the Cat Bypass & Big City Thunder Baffle from Lamont--I have not been able to burn out anymore--2015 F3's appears to have more acceleration after 3000 rpm. Sending my ECU in to Monster Fuel in hopes of correcting the lack of off the line torque. It just may be taking off faster without the burnout but I miss it.
Darrell
PS: I installed the Big City Thunder Baffles approx 1"+ closer to the header area(than shown in directions) but I doubt that should make a difference on back pressure torque.

[CoolSpyder2014]

Back pressure or Velocity for a 998 v-twin, what is norm for backpressure or velocity at idle up to redline for a stock 998, and how do you accurately measure this? I have a Pitbull cat delete and a akrapovic sport touring muffler. I have a possible new idea to make more use of the torque these powerplants put out. But I need more info to start R&D on a variable baffle system. Remember we got rid of the cat to exhale easier and lose wieght. We dont want to bring back the negative factors

[AY4B]

Im sure that the stock Cat has back pressure built in. How does the Cat delete with one baffle and the stock Cat compare in back pressure? Which has more, and by how much? I have a stage one monster flash and also can not spin the tires. Yokohama Tires at 21 pounds cold. I did notice the tire heats up 10 degrees hotter than the front tires according to my FOBO. It was causing my high alert to come on ryding on the freeway yesterday. It made me to start thinking that I need to add a little more pressure to drop the temperature.

[Yukonf3]

Re millerdjr and back pressure. ...Yes I totally agree. It's NOT back pressure causing the problem with a cat delete, it's pulse timing!! There is virtually NO back pressure with the stock system under 5k rpm. I've measured it with a digital manometer. Adding a baffle simply reduces the ill timed reverse pulse created from eliminating the cat. High flow exhaust with the right primary and secondary pipe lengths will always beat artifical restriction. My two bros exhaust and stage 2 maptuner tune will burn the tire throught three gears... no restrictions and good pulse tuning with ecu mapped to take advantage = big power.

[Gwolf]

I left the OEM cat in place and just put an open glass pack pipe on. Got plenty of power to spin the tire up, sometimes even when I don't want to. If I take off a little fast and the tire hits a painted strip on the road or there is some oil residue at the stop lights or sand in the road, it will bark the tire without meaning to do it. Have to stay off the throttle on the dirt roads even in 4th or 5th gear, or it will fish tail. If only I had that kind of power when I was young and crazy, but then I may not have ever got old.