Forum

[Creaky45]

I have just rebuilt my 2006 Classic using a 535 Alloy barrel I bought from our host a few years ago with its matched forged HC piston. For some reason we won't go into here that piston blew a hole in its top. (I know, too lean or too advanced). At the time I could not afford to replace it so I re-used my original iron barrel and standard Indian piston for ages and it went well. (enough)Recently I decided to buy another similar piston from our host. ($300.00 AUD)and have just finished the rebuild using my alloy barrel which has been measured by engineers and is still perfect and 87.0mm. The clearance suggested by the pistons specs is 0.135mm to 0.145mm. My brand new piston was well over that but I installed it anyway. The bike runs fine and has heaps more power but it rattles quite badly (which is what I suspected) and does not get any quieter when hot. I want to know who else has had this experience. I will put up with it if enough people say it's normal and not doing any harm, otherwise I am considering taking the piston and my iron 500 barrel to an engineer who says he can bore it to suit the 535 piston with those clearances stated above.

[Leon Novello]

Creaky says it wasn`t broken until he tried to fix it.

[Revband]

Once a piston/barrel clearance increases due to wear the wear rate increases proportionally, I would think the same will happen here due to the increased clearance.

[scotty]

Hi creaky ive bored an iron barrel out to 87mm no worries, anything I buy from re or after market sellers is checked before assembly, some things arnt up to speci. It realy is buyer beware out there, lots of sus bits around nacelles with wrong threads bent drive shafts big end bushes of various sizes. Methinks QC is only a myth.

[Creaky45]

Scotty, I bought this piston and barrel from our host at enormous cost, it's not an after market Indian one. It is an Accralite, supposed to be the best. I think they are too small in diameter but the spec sheet does not say what the diameter should be. It just says the bore should be 87mm which it is. What could I have done? Sent it back to Mr H at more postage cost so they could send me another exactly the same. I am hoping to hear from someone in the same position who also finds the piston rattly but may suggest that this is normal. Does anyone know what the diameter of the piston should be? And Revband is not giving me too much confidence but thanks for your replies anyway.

[papasmurf]

Creaky45, I learned a VERY long time ago, don't get a bore bored out until you have got the new piston, so the bore can be bored to suit.
Or at least measure the bore accurately so a piston can be purchased with the correct clearance.

[Creaky45]

Sorry Papa but you miss the point. I bought the piston from our host and I bought the barrel from our host. They are supposed to match. I have not bored anything. If I do bore my iron barrel, yes, of course I will give them the piston to get the clearance right when they bore it. So, how can I buy a 535 piston to match my alloy barrel which is exactly 87mm. Do I spend another 300 bucks on an oversized one and then 150 bucks to bore my barrel? I think I'll buy a pushbike.

[papasmurf]

Creaky45, I would suggest contacting our hosts, and asking what the maximum from new piston barrel clearance should be.

(On an air cooled engine the clearance tends to be of the proverbial in a bucket variety.)
The workshop manual for my Electra X has a new bore size of 84.025mm-84.035mm
With a piston clearance min of 0.08mm below that and a max of 0.10mm (Service limit 0.3mm.)

[Alan R]

Hi guys--------- Hi Creaky45, just for the record on page 34 of the very latest Cat. ( 2018 /19 ) we see a "Big Bore Kit" part No}---200074C ( Alloy Barrel with 8.5 : 1 forged piston )...The piston is described as}--"Completely re-designed"...and "When fitted this gives 535cc"........................Is this the item that you originally fitted ?..... and then the piston blew a hole in it's top ??..Did that assembly ever rattle at all ??....Did you actually find out just what caused it ???

Later, you say you ordered another similar piston ( $300 AUD ) .... Would that be the Accralite Piston on Page 32 part No.90020 ??..................Did you ask if this second piston is exactly the same as the first one ?...........I'm wondering if the rattle is a pre-cursor to another failure.....??

[enfield_trials]

i think better you talk to host .. and discuss your case ..