860ccm-Big-Bore-Kit for F4 and BRUTALE

greenspun.com : LUSENET : MV Agusta F4 : One Thread

Hey red-mates, look at: www-mobil-tech.de

They offer a Big Bore-Kit for BRUTALE/ F4 -860ccm -20 PS moore, looks at the Dynos -developed by MV Agusta ...!!!! -cost about 4200€ -it`s the cylinder of the F4, bored up to 79mm -Andrea Goggi from MV developed the e-prom for it, and was deeply impressed after his first test ride on the 860ccm BRUTALE.

Big-bore-greetings from Germany, Gunnar.

-- Gunnar Brunckhorst (gb@hoergeraete-brunckhorst.de), July 13, 2004


Gunnar, this sounds like a nice little addition to any F4 or Brutale. However, it seems that they are too little too late with this kit. Casoli has had their 908cc big bore kit on the market for two years now. And if my conversion works out correctly, it's roughly the same price so you may as well get all you can if you're going bigger.

-- Brian Ogle (brian928s@cs.com), July 13, 2004.

I beleive the Casoli kit only fits 2001 and under as I asked them about it when they did work on my bike. Actually they have a 2001 red and silver with this kit for sale or did. A customers of theirs bike.

-- Ron King (maksuten@earthlink.net), July 13, 2004.

I think the bike you're referring to is a 2002 model. That is precisely the bike I want to buy.

-- Brian Ogle (brian928s@cs.com), July 13, 2004.

Brian are you in Florida too?

-- Ron king (maksuten@earthlink.net), July 14, 2004.

There may be issues with year to year on the Cassoli kit due to piston to valve clearance difference on the various years. The bike sitting up in Clearwater is an 02 model. I know the owner and have sat on the bike. I've contemplated purchasing this bike as well but with MV1000 prices coming in at just under $21 K (with a rash of improvements), it's hard to justify the price. Especially with the question of long- term reliability of the kit still up in the air.

-- Michel Fortier (rx7tt95@aol.com), July 14, 2004.

Ron, I'm in NC but have spoken to Ryan about Tim's bike.

-- Brian Ogle (brian928s@cs.com), July 15, 2004.

In response to reliability issues with the Casoli kit, has anyone heard anything in that regard after say a year or two? Is there anything the big bore kit wears out faster than normal besides the rear tire? Any stories of the motors going pop after several thousand miles??

-- Brian Ogle (brian928s@cs.com), July 15, 2004.

None that I've ever heard of...if the kit is well engineered and weight of reciprocating parts is kept in check, it isn't rocket science. I'd think the biggest problem would be fuel mapping and Tim said that the initial problems Superbike had with the fuel mapping had been solved. Part of the problem was that the stock injectors didn't flow enough to keep up with the heavier breathing. Larger injectors solved that. I'm sure if the gram weight of the rods/pistons is comparable to stock, there won't be any issue with crank flex/excessive bearing wear. I know Tim did tons of work to get this bike right and that it is. Definitely a reflection of one man's passion and it solved many of the shortcomings of the stock bike. He did the best of everything where modifications were made. I keep going back and forth on the bike given the close proximity in price to the 1000 which eliminates engine breaking, uses the larger 50mm Marchozzi's, etc...then again, I'm sure it has a host of parts that will need upgrading, mostly cosmetic, things Tim believes should be on a bike from the factory at the price they're asking. And he's right, there's really no excuse for a $19K bike to come with faux carbon parts. Whoever buys it will certainly be getting a much better bike than a stock F4. Just buy it quick or I might pull the trigger :-)

-- Michel Fortier (rx7tt95@aol.com), July 15, 2004.

O.K. how many of you "experts" have actualy ridden one of these 900cc kitted bikes? I've tested the Casoli kit. They were very gratious to allow me to even ride it (given my reputation) yet alone sending me back out to "put it through its paces" after I'd rolled in with the chain draging on the ground. The bike had noticibly more horsepower but, the additional torque was drastic. Only one problem, it was fairly obvious that 900cc's were never going to work with 750 injectors period. There will always be a flat spot at 5-6. Cams, exhaust, chip, etc. are never going to solve the problem completely. The 860 kit maybe less drastic. Now if someone were to use either kit (particularly the 900) combined with the right cams, exhaust and 1000cc injectors and chip you may end up with a bike that works better then the 1000. Why you ask? Less torque = less wheel spin on the small part of the tire (lower down in the powerband) and better drive out of the corner with a top end punch when the bike is at less lean angle and on the large part of the tire. If I try it out I'll let you know. Ciao Sean Crane ex AMA pro roadracer

-- Sean Crane (buyordieunlimited@hotmail.com), July 16, 2004.

So Sean, since you had a chance to ride it, what were your riding impressions? Would you recommend the 908cc kit over the stock 750 if money was no object?

-- Brian Ogle (brian928s@cs.com), July 16, 2004.

Actually I was offered the opportunity to ride Tim's bike but turned it down. I seriously, seriously doubt it'll work better than the new MV 1000. Being the "expert", have you ridden one of those?

I really really hate speaking for the owner but one of the reasons it's for sale is that he feels his twn bikes (V-twins) work better on the street than the MV. He could have any bike and yet the MV is up for sale. I'm NOT saying the MV is bad and I don't think anyone in any of the topic posts said that (so I'm not sure where your "expert" comment is coming from) just that MV had quite a bit of time to develop the 1000 cc engine and package on the racetrack over a few years. Logic would naturally dictate one to pick the new 1K bike over a big bore 750. Now for him it's just personal preference (twins over an inline). For me it's a cost comparison. None the less, I am considering the purchase of the bike.

-- Michel Fortier (rx7tt95@aol.com), July 19, 2004.

The 'Casoli F5 Rosso' that I own is a substantial improvement over the standard 750.It has more torque and remains tractable in traffic,the power is raised but appears higher in the range and with open pipes is very loud. There are two main issues that mark it out from a factory prepared machine - engine temperature is raised considerably in traffic - although still with in limits and the fuelling at 6000 rpm gives a flat spot - similar to a two stroke power band - you just have to adapt your riding - keeps the revs up,hear the engine wail and grin like an idiot. All in all the conversion of the 750 is a worthwile activity but the introduction of the 1000 does pose a dilema - modify your 750 or get on the list for a 1000? I reckon if you have a straight 750 you should do the mods and enjoy the experience of working on your bike and making it uniquely yours,after all the 1000 looks the same.I'm sure Casoli can provide all the parts,advice etc that you need.

-- Peter Fox (peterhellworks@aol.com), August 02, 2004.

The bike featuring the big bore kit here in Florida (it's a 2002 model) has upgraded (read larger) injectors and new mapping. Perhaps it's something Casoli can get for your bike too. Superbike, makers of the big bore kit, did the work on his bike which took some time due to the need for new injectors and mapping. Injectors that are too small won't cause a stumble in the midrange. That's mapping issues plain and simple. They will run a much higher duty cycle, probably too high, in order to meet the fuel demands. I'm not sure what type of injectors the MV uses (assuming they're top feed pintel units) but the end result can be an overheated injector that locks shut. But this would only happen at WOT at the top of the rpm range, not in the midrange. If it's a two-injector per cylinder system, the second injector coming online at WOT at a predetermined rpm point could also cause a hiccup if the transition time in ms isn't smooth or they don't atomize properly. I'd contact Superbike directly and see if there's an "update" for your bike available.

-- Michel Fortier (rx7tt95@aol.com), August 02, 2004.

Here's the link to Superbike Racing. http://www.superbikeracing.com/

-- Michel Fortier (rx7tt95@aol.com), August 02, 2004.

I'm not sure if Doug Lofgren did the final tuning but he definitely had a hand at points in development on the Casoli kitted bike.

Some reading on his site here:

big bore: http://www.visi.com/~moperfserv/mv900.htm

750 WCT chip: http://www.visi.com/~moperfserv/mv_mapping.htm

He speaks to some of the issues discussed here in detail.

-- James (jamesacorell@hotmail.com), August 03, 2004.

Ah, thanks for posting! I read those articles some time back and had lost the link since...I do remember some discussion that Superbike went "outside" to another source to finalize the new mapping with larger injectors. It took some time, about six months using Tim's bike I believe. He wasn't happy with the time lapse, but in the end, he knew the bike was "right".

-- Michel Fortier (rx7tt95@aol.com), August 03, 2004.

I will be parting out the 908cc F4 soon (pretty stuff only). I never liked the MV750 for the street. I guess that I'm a "big twin" guy, and like low end grunt, especially on the street. I find it hard to wring the neck of an in-line four with out attracting a lot of attention from the law. With such an anemic mid-range, I found myself riding around using only first and second gears, and still going slow. By the time I got the kitted bike back, I had started riding an Aprilia Mille on both the street and track. Lately, I have spent a lot of time racing a Kawi. 636, and I've been curious about how the MV would perform at the track. My MV has been sitting at Cassoli for a year now, while I've raced (and wrecked) an ' 03 Aprilia RSVR. and a 636. I now have an '04 race bike (Aprilia), but I've kind of gotten used to a screaming in- line four. Anyway, I'll be stripping anything unnecessary off my MV and making it a track/race bike this week. It's still supersport legal (as long you guys promise not to tell anyone about the extra cc.s:), so I might try to give those Gixers a run in Formula Forty. Sadly, I lack talent more than horse power. Regards, Tim

-- Tim Anglim (timanglim@earthlink.net), February 14, 2005.


In consideration of your personal experiences riding twins and inlines, please offer an opinion for me.

Upon my initial adjustment to riding a 750 I-4 after years of a Rotax v-1000, I have found the powerband’s sweet spot and am finding considerable joy keeping my Brutale hot in mid-high revs. However, I wish the anemic low-end flat-spot could be dialed out. I am not chasing wheelies nor do I want to drag race from every standing start. However, wringing the throttle in first and second just to keep up with cages jackrabbiting for stops sucks when I’m simply dealing with city traffic. The same disappointment is sometimes realized when accelerating on to a freeway. Concurrently, light trail- brake with correct engine speed plus mid-corner roll-on throttle makes riding my art piece very enjoyable. Also, at speed throttle blasts from 7k-rpm have been known to send my nipples back to my shoulder blades. Truly exhilaratingly fast. And the music? Gorgeous!

I am thinking of investing in a full open exhaust a re-chip. The thought of increased displacement is interesting but not a first choice option. Please ramble on a bit. Thanks.

-- Leonardo (lpasq@hotmail.com), March 08, 2005.

Moderation questions? read the FAQ