Flat spot around 4000rpm

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Does anyone have a very noticeable flat spot around 4000rpm?My 1200 mile bike,(UK model, 1+1 year 2000) is new to me and its most annoying when in traffic.Whats the solution apart from screwing harder in low gear.Bike performance in every other respect is about perfect.

-- jonathan milner (jonathan.milner@bt.com), October 04, 2001

Answers

Jonathan, I have a similar spec bike with 3000 miles, had it since new and I have not noticed a flat spot. It is true to say that not much happens at low revs (and 4000 is low). However in town I find the bike behaves fine and I tend to be around 2 to 4000 rpm most of the time. It does of course depend on how fast you want to accelerate ! I have spent most of my time on twins so expect to use low rpm, I find it hard to wring the bike out so I would have expected to notice a problem. What does your dealer say? By the way, make sure you take it to one of the good ones, the reports are very variable. I have heard that HR Owen, Powerhouse and Baines are the best. ( I use Baines and they techie there knows his stuff) rgds willy

-- willy (ginnyoneuk@yahoo.co.uk), October 04, 2001.

I think most owners do have a flat spot between 3500 - 4000 rpm. Some have been able to decrease it by adjusting the FI sensors. I'm like you, it's damn annoying. I compensate by dropping a gear lower and revving higher.

-- Brad Cowell (bcowell@cswnet.com), October 04, 2001.

Most of the articles on the MV commented on a very fluffy low end and mid-range (under 5,000 rpm to 6,000 rpm). I heard it may be due to the fuel injectors or computer chip.

I wonder if it's improved with the 2001 or 2002 models.

-- Allan Gibbs (Agibbs996@aol.com), October 05, 2001.


Mine's a 2001 model, and it has it around 3500 rpm. It's annoying, but not too big a deal. It's all worth it after 7000 rpm!

-- Brad Cowell (bcowell@cswnet.com), October 07, 2001.

Hey Guys,

If you really want to cure this problem of flat spots you need to get an electric golf cart...preferably one that looks like a miniture Rolls Royce.Electric engines peak torque @ 0 rpm.That should do it.

-- C Thompson (cthompson@yahoo.com), October 16, 2001.



Jonathan,

My 2000 model has 1K miles and has had the infamous 4K flat spot since I had it new, its nearly pitched me off on a few occasions pulling off from junctions. It had its first service at Powerhouse, who's top man just acknowledged the flat spot after taking it for a blast but could do nothing to sort it. Regarding the possible cures, I've tried all these under warranty....new computer, new injectors, new leads, new plugs, none of which in my case sorted it!

Any later advice gratefully recieved.

-- Dave Penhale (DAPPER@dpenhale.freeserve.co.uk), November 17, 2001.


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