JE V's Wiseco Pistons? - 900 V's 944?

[MonsterMadMarty]

I'm looking to replace the pistons in my M900 and would like opinion on JE and Wiseco pistons? Also, should I stick with standard 92mm bore or go the 94mm bore? If I go the larger bore is it just a case of getting the cyclinder heads bored or is there more to it?

Cheers in advance 

[ducpainter]

I got nuthin' on the relative advantages of the two brands.

If you go overbore you need to have the cylinders re-plated with nikasil.

Not an inexpensive proposition.

[brad black]

owned by the same parent company. 

if you are referencing 87mm wiseco pistons then they're 1mm oversize 860/900 bevel drive pistons.  std bore on a belt drive 900 is 92mm.

wiseco make the ferracci pistons afaik, otherwise i don't know of any wiseco 900 belt drive pistons.

[MonsterMadMarty]

owned by the same parent company. 

if you are referencing 87mm wiseco pistons then they're 1mm oversize 860/900 bevel drive pistons.  std bore on a belt drive 900 is 92mm.

wiseco make the ferracci pistons afaik, otherwise i don't know of any wiseco 900 belt drive pistons.

Ooops..... My mistake, I meant 92mm now edited original post.  Thank you 

In saying this, can anyone clarify for me the std piston size of the M900 carburettor engine? All reference to 92mm seem to only cover the injected engine 98' on!

I have a two sets of 92mm rings Ducati part number: 12120291B which I've been told won't fit my pistons!

[Speeddog]

Standard piston size of 900 is 92mm.

Are you sure about that part number?

It supersedes to 12110401A, but it's described (and priced) as a piston pin.

[koko64]

JE pistons are very well priced by sponsor California Cycleworks. If it's not a "maximum effort" build requiring more capacity, then stock 92mm bore hi compression pistons are a great bang for buck modification.

I am running JE 92mm pistons in my '95 900 Monster and my brother has the same in his 2001 M900SIe. We are very happy with the performance increase.

Going hi compression on a carbed 900 will require an ignition adjustment and 98 fuel to be safe.

[MonsterMadMarty]

Standard piston size of 900 is 92mm.

Are you sure about that part number?

It supersedes to 12110401A, but it's described (and priced) as a piston pin.

Yea, positive the part number (as stated on the box) is: 12120291B PISTON RINGS BAG 900 M/00

[MonsterMadMarty]

JE pistons are very well priced by sponsor California Cycleworks. If it's not a "maximum effort" build requiring more capacity, then stock 92mm bore hi compression pistons are a great bang for buck modification.

I am running JE 92mm pistons in my '95 900 Monster and my brother has the same in his 2001 M900SIe. We are very happy with the performance increase.

Going hi compression on a carbed 900 will require an ignition adjustment and 98 fuel to be safe.

Cheers, sounds good I'm not after outright horsepower, more a case of same power as before with less effort. If that makes any sense! Of course the extra power is handy.

[koko64]

Stock low comp pistons would let you run 91 fuel and not have to frig around with the timing I guess.

[monsta]

So, Its not power your after its torque?
Torque is where the funs at with these bikes....

[koko64]

I bet your M984 has some grunt.

Increasing the compression certainly increases torque. A pair of flatslide carbs also enhances response.

[MonsterMadMarty]

So, Its not power your after its torque?
Torque is where the funs at with these bikes....

It's all about the torque 

[almgren.t]

I have JE high comp 92 mm pistons and FCR 41:s in my -99 M900. Butt dyno says it pulls much stronger than stock and is more responsive. However, it is hard to judge how much more power and torque it actually delivers compared to stock, really. It is more fun than stock for sure.

[koko64]

Brad's bikeboy site has a before and after for an M900 with high comp pistons. It's a substantial gain.