an 400 engine knock,not big end!

[redmires]

Hi ,can anyone shed some light on the two engines I have ,after buying them on eBay,for a considerable amount,I put them in the bike and they both knock,the noise emanates from the crankcase,but the cranks on both are ok,that is no sideways movement or play on the crankpin bearing,all seems good apart from this damn knock.I have seen a Youtube video on one burgman with exactly the same noise,but found no answer to this.I think the cam chain/adjuster/guides,they all look good,but I took the adjuster out,had a cuppa,forgot to put it back in,started the engine,it ran but all the crankcase pressure came out of the orifice,lol,put the adjuster back in ,the engine ran quiet for a couple of minutes then the knock came back.Any ideas would be most welcome.Oh oil pressure is good!.

[johnp]

It is polite to introduce yourself first before asking any questions.

[Dave Weller]

Welcome, If the engine ran quiet for a couple of minutes, you put the adjuster back in and the knock came back, is it a fuel injected model, is the oil pump working or are the engine sensors adjusting the timing far to advance.

[redmires]

Listen guys I'm a 58 yr old technophobe so I'm sorry for not introducing myself I don't even know where to do that,my name is Paul,Yorkshire lad born n bred,ridden bikes all my life from being 17,was retired on ill health in 2008 with spinal stenosis after working as a diesel mechanic on buses for 28yrs.The answer I am seeking is about an AN 400 ,the 385cc model,no injection,oil pump very good, big end sound.I had it out yesterday,11th September,after building all the bodywork back up,it pulls like a train,but with an annoying like almost diesel clatter from the crankcase,the top end is fine,excellent cam etc.So new to Burgmans,I'm at a total loss of what this noise is,but I googled youtube the other day,same noise same bike engine,on video,so I'm not alone on this one which actually gives me little comfort.I did however have to change the woodruff key on the genny,as this had sheared,making the bike impossible to start,but as soon as I had replaced that,the engine fired into life immediately,I bought it not running,took me ages to find the fault as I'm better on Rolls Royce,Cummins,Volvo diesels lol.Hope this sheds a light on the problem?

[michaelphillips]

hi mate, just a thought, so could be completly wrong i was wondering if the noise could be from the front rollers in the transmission, as these are inside the variator which in turn to the bottom of engine,, if owt in there is not tight could cause the rattle/noise you describe. the variator nut could be loose or the roller sliders could be damaged etc, just a thought

[Dave Weller]

Does the noise go away when it is revved up, that should prove if the rollers and sliders in the varidrive are at fault. Is the new woodruff key tight, or the rotor could be rattling.

[michaelphillips]

Does the noise go away when it is revved up, that should prove if the rollers and sliders in the varidrive are at fault. Is the new wood ruff key tight, or the rotor could be rattling.

it would be prudent to take the casing off to have a ganders as not been on the road for a while, for a good inspection,

[kishan]

welcome

[Funkycowie]

Hi!