LRD did all the work on my 440. Work included full exhaust, cam, big valves, carb, piston, sleeve, 8 plate clutch, all gaskets, all labor for porting, boring etc....everything, hard facing rockers, stiffer valve springs, was about $2,500.00 even included 1 gallon of race oil and a t-shirt.

 

I have only had mine since Sat. (18th) So I cant talk about reliability yet. But I will say that I have a 11:1 piston and have no problems running on premium pump gas. I think what you buy were you buy it and who installs it is crucial. All 440 kits are not equal! It is like any other motor that you can modify. Matched components are critical. Do not mix and match parts. Talk with a tuner or someone truly qualified to give advice. I could have saved money and installed the kit myself but I knew that I would not be able to set it up like a professional. I also do not trust dealers to install something like this. They will not take the time to jet and tune the bike properly once it is installed. Call Lazarus at GT Thunder you wont be disappointed. You might be better off to e-mail him because he is hard to get on the phone cause he is so busy.

 

400EX4fun,I never had mine on a dyno and as far as HP I don't know .It was a cold natured bit-h at times also as norcalatver said.I would have a Warrior drag it around to start,but after it was warmed up it would start on its own.As far as comparing, on a 3X run against a stock Raptor to 300' on the blacktop the Raptor lost all 3X by between 1.5 to 3 bike lengths.I believe it would have wiped me if we would have been going much further down the road!!! The stock gearing just wasn't up to it on the short run..I have nothing bad to say about the 440.I am not a wrencher and purchased it complete.Now we see what Fraker Racing can do with this Banshee I purchased 4 hours ago.Good Luck Extreme...

 

I dont own a 400ex but,a few weedends ago at buttercup dunes I got a chance to race a ims440ex at comp hill.It run very well. that day I raced maybe 5 or 6 400ex's stock and with aftermarket exhaust,I was beating them on my 99 sport by about 8-10 quad lenths.
Then got to race the 440ex he got me...my front tire was about at his foot peg,the fastest EX that I have raced up the hill by a long shot

 

Hey Narcleatver, $2500.00? Thats alot to spend on some engion mods. Everyone elses is under $1000.00, what happened there? And EXlarge, so you only bored yours oout .80 over, switch your compression, bought a new piston, and had it polished right? Do either of you two have any dynos or have you been clocked or anything? I am just looking for numbers. Thanks

 

I have a 440EX and I do have dyno sheets before and after the kit. It is an IMS kit. The rest of the machine is stock except for a K&N filter and jet. I can't remember what the HP and Torque values are but I seem to remember that the HP after the kit was around 26.7 and the Torque was 27.5. I will have to get the dyno sheets from my shop. I will say one thing, the 440 vibrates. This has the potential to be detremental. If I could start over, I would install a 416 kit and then do the port work, cam, carb,exhaust, etc. If anyone wants to email me with their thoughts, they can. Over the winter I plan to port the head myself, only because I know what to do, and some other mods. I will keep you all posted as to the outcome.

 

After being bored .80 over, how many cc's would this equal to compared to the other kits?

 

I do NOT have a 400 or a 440 kit, but I say what the heck, do it!, you can always have it resleeved! ;-)

 

Well, I'm not totally convinced yet. I am leaning toward CRC400ex's idea of having GT Thunder do the work by installing the 416 with piston, porting, GT cam, and rejetting with dynotest results.

Seadooman, please reply back with your dyno's....somethings rotten in Denmark...stock hp is around 28. Anyone else complain of the vibrations?

The other factors leaning at the 416 is the margin of rebuilds in the future are roomier. Also, I've heard complaints of clutch basket weakness and other internal concerns that could cause some big money issues with the 440...any thoughts?

Lastly, everyone seems to be running different piston ratio's and cams...no matter what kit....why so inconsistant?

Any 416 guys out there?

 

.80 over equals 416