HHm PRO Series Cylinder Kit 72mm YZF R 125 V1-V2 - MT 125 V1
The HHm cylinder kit benefits from a 72mm bore, offering a displacement close to the 239cc in the original stroke, and it is possible with a long stroke crankshaft to have 251cc to 304cc.
It will fit perfectly on your Minarelli LC 125 4T high engine (YZF R125 2008-2018 and MT125 2014-2019). To complete the assembly, a cylinder head with 22/25mm Fasstek valves is strongly recommended. A cylinder head with 24/27mm or 25/28mm valves is possible in assembly provided that the original piston is machined, but it will be necessary to carry out the usual checks in squish metrology and valve/piston spacing.
The cylinder skirt benefits from 8mm more than the standard cylinders, i.e. 33mm in total length, with a radiant cut for the passage of the crankshaft masses.
However if you want to put a long 61.7mm Fasstek stroke there will be a little machining to do on the skirt (about -1.5mm), but for the 68 and 74.7mm stroke this one went up without any problem since it you need to put a base wedge.
The cylinder benefits from a ceramic treatment in order to offer better resistance in all possible engine speeds, and from a high compression forged piston with a conical dome in +2.40mm on the flat compression part. With an adequate intake engine and electronic configuration, it is possible to approach 32 HP!
The HHm kit comes complete with cylinder, piston, segments, rods and pin.
Please note: you must purchase an additional set of seals in connection with the cylinder which will be offered to you as an option.
LAB Fast125 Tech Tips:
- Machining of the casings is mandatory to allow the cylinder skirt to pass.
- We recommend adding a Racing oil pump and fitting a new timing chain. (see also chain guide pads)
- It is possible depending on the version of the engine that the cylinder requires a Manual FST timing chain tensioner, for this please look at our photo in comparison with the one that is already mounted on your machine.
- For the replacement of your cylinder you will need to provide for the dismantling of your cylinder head and the ancillary connections.
- Before reassembling your high engine, we advise you to check your squish and the valve/cylinder head/piston gap with your camshaft and to torque tighten the 4 cylinder head screws, the tightening of which is 22Nm, and for the 2 screws on the water pump side a 10Nm.
- For motorcycles with high mileage, we recommend that you purchase a water pump repair kit and cylinder head screws!
- We also recommend that you put an adequate injector in relation to the engine capacity and well-proportioned intake accessories (throttle body, air box connection, air filter, fuel pressure regulator, etc.)!
- We advise you to fit a Powertronic programmable ECU in order to refine your engine tuning.
- A forged connecting rod or a crankshaft with forged connecting rod is mandatory for engine reliability!
Please look at the vehicle table below, in order to see the possible fitment!⮷
(Rare product so ask us if out of stock)
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