Best Exhaust System?

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Do any of the available exhaust systems really cure the miserable low RPM problems the stock bike has? My dealer says that a new exhaust system and chip will cure the poor bottom end but every bike I've ever owned that got a new pipe and jetting actually suffered on the bottom end and improved up top. All the fun is in the bottom and I couldn't care less if I gain 5 horses at 14,000 RPM. I'm sorry but I think the bike really sucks and I'm feeling like fixing the problem will cheer me up but I hate to spend $1500 and have the bike suffer even more on the low end reponse. Has anyone upgraded the exhaust and chip and noticed an improvement on the low end? I've never owned a sportbike that couln't do a first gear power wheelie (no clutch) and I never dreamed this would be the first one that couldn't!!! .

-- Sean Edwards (t22_7@msn.com), February 15, 2002

Answers

If you need to do first gear wheelies (without use of a clutch), buy a bicycle. They're great for riding up city blocks on their rear wheels. The F4 was designed for riding at high RPM's at high speed on open roads (tracks). I installed the CRC open racing pipes and chip and noticed a "seat-of-the-pants" improvement in the low and especially middle range of the power delivery. It's hard to tell what the gains, or lack thereof, have been on the top as I haven't had the opportunity to get past 145 mph in a while.

-- Chris Eden (biospeck@mindspring.com), February 15, 2002.

I think you're probably misguided in using the first gear wheelie test. This bike puts a lot of weight on the front wheel, so that makes a difference, as well as the power.

But ultimately, who cares? The bike is what it is. Tweaking it probably isn't going to accomplish what you need. Small bore inline 4's are soft on the bottom. Especially ones with super short strokes, as the MV has. Get over it. I have an R1 that will do first gear power wheelies, but rolling on the power coming out of a corner upsets it infinitely more than the smoother (and softer) delivery of the MV.

If you buy a bike needing to do major modifications right off the bat (and you don't race it), you probably bought the wrong bike by my way of thinking. Ergonomics excepted.

(I personally like free flowing pipes because I subscribe to the "If they can hear you they can see you" notion)

Andy

-- Andy R (quadreverb@yahoo.com), February 16, 2002.


The only reason I mentioned first gear power wheelies is because they really are an excellent test of how well a bike performs off the bottom end...not because I'm a street squid who should stick to bicycles if I need to show off. Sportbikes are intended to have a decent off/on throttle response when pulling out of corners around a racetrack and the MV suffers greatly in this area when exiting slower corners unless the thing is wound up. There is no reason to make excuses for this bike and not compare it to Japanese multis that all kick its ass hands down. The MV will do a fair job in comparison but requires much more work to keep it in the power due to its weak bottom and mid ranges. Sure it is what it is and I agree..I may have bought the wrong bike. I just don't see any reason to cut it some slack becuase its got a pretty face just like some high maintenance woman who will ultimately drive a man insane.

To the other guy: Thanks for the input on the CRC system. From what I've heard it sounds like the most likely alternative to give me what I'm looking for. Who knows? There could be something wrong with my bike's fuel injection system and everyone else's bike may be running stronger than mine after all.

-- Sean Edwards (t22_7@msn.com), February 16, 2002.


I've put nearly 3000 miles on my MV over the past couple of summers at tracks around the US. I too have found the MV to really struggle when exiting slow corners. I'm having the pipe and chip fitted this week, more for the music than anything else. The best solution for improving slow corner exits is to go with a larger rear sprocket. Makes far more improvement than anything else. At most tracks it doesn't matter that the bike will only pull 150 instead of 165.

-- Mark Westlake (mwestlake@powerway.com), February 18, 2002.

Does anyone know where different size sprockets are available other than through Cagiva/MV? I was hoping maybe someone had bought sprockets from someone like Renthal or Sprocket Specialists. I'd like to add at least 2 teeth to the rear and possibly change the whole bike over to a 520 chain/sprockets set-up.

-- Sean Edwards (t22_7@msn.com), February 18, 2002.


www.mvagusta-sp.com/indexuk.html has the "official" front and rear sprockets for sale. I order some parts recently and they arrived in under a week from Italy to New Zealand. Payment can be made by Visa/Mastercard.

-- Matt Thompson (matthewt@nitor.co.nz), February 18, 2002.

look at QB Carbon UK... there is quick-change sprocket carrier

-- Dean Miljkovic (Basta916@aol.com), February 21, 2002.

The MV comes with 520 chain/sprocket combo from the factory.

-- ben kifle (ben_kifle@yahoo.com), March 18, 2003.

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