This G2 replica kit is a copy of the real GR2, obviously much less efficient than the real competition! The real competition GR2 (G2) has a forged piston in mono segment, a bar escapement, track digraphs ...
This kit being a copy made for the road is more solid, the bar exhaust has been replaced by normal exhaust, the exhaust thread is no longer for large ball joint of 38 but for ordinary ball joint, the piston is a dual model Hard chrome domed segment, this bi segment significantly slows the high speed and promotes torque, wear is therefore much less intense.
The piston is slightly reopened on the back to promote sweeping. It is identical to the G1 replica but in liquid cooling, which offers additional security of power and strength in addition. The cylinder is in high-end aluminum and treated nykasil, the bore is 39mm like the origin so it develops a displacement of 50cc, it has 6 transfers and a normal exhaust.
Where this kit is very valuable is that it preserves the form of transfers to the base and the conduits of the real GR1 and GR2. So increased transfers on the front, this form really offers maximum performance, you will obviously have to align your crankcase with this kit . The cylinder head is a turned chamber model, polished hemispherical, in high compression, it is perfectly designed to the cylinder / piston with a ratio of 11.8: 1.
This kit is really very powerful, solid, it will offer you a very good torque and fairly good high speeds, the diagrams are well served. We will only regret that there are not several joints to perform the squish (you can install the base joints of the G2R / GR2)
Diagrams and technicalities:
Material: nykasil treated aluminum
Designed for stroke: 41.80mm (original MBK 51)
Diameter: 39mm
Actual displacement: 49.93cc
Lightweight MALOSSI model piston with internal cooling fin
Segment: 2 thick 1.5mm hard chrome domed for less friction
Transfers number: 6
Exhaust: normal width 100 °
Chamber volume 6.5ml (for 2.5ml long pellet already removed during measurements)
Hemispherical chamber (chamber Ø29)
Exhaust diagram: 184 °
Side admission diagram: 130 ° number 4
Rear intake diagrams: 117 ° number 2
Compression ratio: 11.8: 1
Recommended cylinder head tightening to the dynamometric: 1.2 kgm
Ignition advance recommended with an electronic DUCATI on MBK 51 / av10 motobecane: 1.5mm before top dead center
Recommended break-in: 250km
View of the crankcase preparation to be carried out :
Preparation advice: Mount the exhaust diagram at 188 ° in order to obtain excellent high speeds. In general, we recommend a side exhaust difference of 60 to 65 ° and this preparation will therefore bring you closer ( D: 58 ° )! The exhaust opening angle is 100 ° so it is good but can be increased to 105 ° and the shape is correct but can also be improved. The base is excellent and very worked, the finish is pretty good! Exhaust polish and piston crown tightened as good.
We recommend it with at least : 17.5mm minimum carburation, reinforced bearings and crankshaft, racing exhaust, cold spark plug B9 for running in / adjustment then B10 (especially with the 1.5mm advance recommended by Malossi), preparation of the engine casings.
The pack contains :
Piston bi segment d.39mm
2 segments d.39mm
Piston pin Ø13mm
2 piston clips (pin rings) in C d.13mm
Cylinder 6 transfers G2 replica aluminum d.39mm 50cc
High compression cylinder head
Complete seal pack
Notice
Stickers
Spare parts :
Cylinder head O-ring pack
Pack seal others (paper base and cylinder head, exhaust ...)
Piston
cylinder and piston without cylinder head
Ax + Clips
2 segments Ø39 by 1.5mm
Cylinder head
G piston clips
As an option we offer a stage 1 preparation, this preparation is a modification of the exhaust port by increasing the diagrams and improving the duct, it increases the performance of the cylinder. Allow a little extra time for this preparation!
View of the prepared version:
In addition to this, you need to know more about it.
