big end

**jim tt600** · #1 14th September 2006

Hi All,well is like this ive just stripped the top end down having a rebore to 97mm
and head gas flowed for a bit more power,checking the big end bearing
there seems to be a bit of play side to side and a fraction up and down,
before the strip down the engine run fine no rumbling noise or knocking
it made every other noise but no knocking sounds,what do you think
new big end,how hard to change crankshaft.
thanks jim

**aukeboss** · #2 14th September 2006

I've bene in this position often: there is no obvious reason for changing your bigend if there is no strange noises coming from there. The only reason that they fail is lack of oil.
Alternatively, if you are going to squeeze more power out of your engine it is probably not a bad idea, not involving that much money (conrod + bearing, 150 EUR, plus gaskets for the open / close work on the engine). But, :-) you'll probably find some other items that are sensible to replace if the negine is open anyway.

So, if you're heading for a long trip, replace, otherwise, put back and keep listening to the noises.

Auke

**jim tt600** · #3 15th September 2006

thanks for reply,i just swapped a piston for crankshaft with a chap off ebay
when arrives ile check the play in that big end and compare the both, is it a big job to change crank