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Montesa 4rt Piston Changes

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Hey Guys,

I've got a 2005 4RT that had new a piston back at the end of April 2006.

The bike was not used by the previous owner for 4 of the months in between (broken hand) and i havent used it for 2 months (broken finger) (yes - the bike is possesed LOL)

How much can i expect to pay - and do i need to be exact on the dates (1 year for piston change according to manual) or is this something i do when i notice smoke or something?

Any advice appreciated :o

Jza

This is something I asked on this forum before I bought the bike (new). I was reassured that this recommendation could be largely ignored and that it was most likely generated by the motocross version of the motor (New rings at 6 months new piston at 12 months is a minimum when racing)

Unless you are riding at a very high level, trials bike motors are relatively unstressed and should not need this level of maintenance. I watch my oil, if it becomes contaminated quickly then the rings / piston are worn, if it doesn't, they aren't.

The manual also suggests regular replacement of the spark plug and the cap. Again, I go on condition for the plug, but I do re-gap it every 8-10 trials. The plug cap question sits at the back of my mind, niggling away. (I have an occasional missfire, -actually it misses 1 or 2 revs then re-starts- that I can't track down, always at low rpm, not predictable or repeatable, never yet under load) I just can't imagine that he problem is in the plug cap

  • Author

Cheers mate - good advice thanks!

I ride like a wuss so i'll keep an eye on the oil as you suggest

Jza

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