New M4 slip on installation.

I have an 07 SV 650S and installed a new M4 Slip on, took it for a ride and here where I got surprised, old top speed on a level 128mph stock, with the slip on 126mph, and it took a bit to get there compared to the stock pipe it got to 128mph quicker. I feel the reason is due to the loss of back pressure, the M4 has a large diameter baffle, the question I have is I called the M 4 tech and they say they don't feel I lost power, it almost seems like I went up one tooth on the front sprocket, it just don't have a pull it use to have, M4 recommends I install a power commander, I really don't want to go that route, so I want to try something, I wonder if anyone has felt the same when they installed a slip on, I want to make a cone to add the end of the slip on tip with a smaller hole to give me some back pressure, any thoughts on this,

Chet

You dont need a power commander but I prefer them when it comes to re-mapping. If you go to a suzuki dealer they should be able to remap the stock sv650 electrickery bits for you. It may also benefit from a performance air filter. However, I do have to ask..... why would you care about losing 2 mph???

a.) its not legal
b.) the sv was never designed to break land speed records!

Hello Sideshow46

it not that I lost the 2 mph, but to boot I lost the hard pull it had when I crack it at 60 mph, and the matter I spent $300 for an improvement, I personally feel the baffle diameter is too large for the small 650 twin, this is only my feeling. but I am going to make a cone and put it in the tip of the pipe to see if I can get some midrange power and my lost torque back, my buddy has a 1200 Sportster, and he felt the same way, I used to be able to gradually pull away form him and now I notice he stays closer to me.


Chet


is that Reading in the US or where!

Reading UK, Chet, this is a mainly UK site.

[Red Herring]

Chet, the only way you are going to measure the size of performance changes you are talking about is to stick the bike on a dyno. 2mph on the top end is not enough of a performance change for you to feel through the "seat of your pants" as the saying in the UK goes. Your perception is more likely to be influenced by the different noise the new exhaust makes. I've also seen bigger swings in performance just by changing the brand of fuel I happen to have filled up with.
I wouldn't go sticking anything in the end of the can. M4 have a very good name and know what they are doing.

Originally Posted by Chet

took it for a ride and here where I got surprised, old top speed on a level 128mph stock, with the slip on 126mph, and it took a bit to get there compared to the stock pipe it got to 128mph quicker.

Same road? Same temperature? Same wind direction? Same wind speed? Engine throughly warmed up both times?

The above are just a hndfull of factors that come into top speed readings, and that doesn't include the over reading SV speedo!

As for the M4 can I would recommend that at your next service drop a BMC air filter in and get the dealer to adjust the OEM fuelling slighty. A PC is an overkill with the SV as the OEM fuelling can be altered enough for common tuning, I would only recommend a PC for the SV if you had seroius engine tuning only!

[quote=Dangerous Dave;1512531]Same road? Same temperature? Same wind direction? Same wind speed? Engine throughly warmed up both times?

+1 ther.

A remap will make it feel much better.