GB is not OK!

[Greybeard]

A box of bits arrived from Fecked.

I think it's pretty cheap of the current owners of the Hepolite name to print the box dirty, as though it's NOS!

[bsa-bill]

Just love those Hepolite packets and boxes, they look like they've been kicking around on a shelf for the last 50-60 years

[Greybeard]

Just love those Hepolite packets and boxes, they look like they've been kicking around on a shelf for the last 50-60 years

Sarcasm?

[RogerSB]

Without taking the dratted cost into consideration I bet you're looking forward to rebuilding now .

I'm certainly looking forward to following your progress.

[bsa-bill]

Sarcasm?

not intended GB, I think the number of the Hepolite boxes that come out, they can't be original anymore, so somebody has their eye the value of nostalgia (full marks to them), now your going to tell me they have been sitting on a shelf for decades

[Greybeard]

The modern Heoplite boxes have grease marks printed on them. This is surely to try to con the buyer into believing they are new old stock.

[Greybeard]

Without taking the dratted cost into consideration I bet you're looking forward to rebuilding now .

I'm certainly looking forward to following your progress.

I'm touched, (we know that GB!) that you care Roger! I'm still planning to get to Norfolk BSAOC camp, weekend after next. I'm still waiting for some more parts but I intend to get on with stuff tomorrow and probably as much time next week as 'She' will tolerate.

[Triton Thrasher]

The modern Heoplite boxes have grease marks printed on them. This is surely to try to con the buyer into believing they are new old stock.

I’m sure they don’t expect to fool anyone.

It’s just a bit of retro chic.

[Greybeard]

Got a chance to go out to the shed this morning. The barrel that was scored has cleaned up with a 5 thou skirt clearance. I am happy about that.

[Greybeard]

Valve spring compressor via eBay has arrived. Even more parts arrived today.

I've had this expanding reamer in my odds-n-sods box for ages. I've cleaned it up this morning. It appears to be suitably sized for the A10 small-end bush. This means that I've probably had the tool since I rebuilt my Ariel Huntmaster waaay back in 1966. What do you say about using this reamer on my bike? The blades may not be extremely sharp anymore as they've been in a box of other tools. I'm worried about getting judder in the cut. Should I be looking for a fixed size reamer?

I found this thread:
https://www.a7a10.net/forum/index.php?topic=10506.msg78055#msg78055

I should be able to use my pillar drill as a rigid table and reamer holder to get the cut accurately at right-angles. (I'm not planning to use the drill motor!)

[bsa-bill]

I've got a set of them in a wooden box GB, have used them for stuff other than engine or fast moving bits, I now what you mean by judder, but my concern is/was I could  not work out in my head if they reamed parallel or slight taper, has to be parallel of course but you know if you sow a seed of doubt it grows, I satisfied myself by reaming from each side - ah what happened to the unbound confidence of youth 

[terryg]

I'd entrust reaming an urgently needed small end bush to a competent machine shop, but that's based on my experience of judder with an adjustable reamer. You might easily be better at it than me, which would not be difficult.

[berger]

I went to the pub at 2-30pm and fell through the door at 1am [*** ed]I am ill! yes in the head.. I like your new toys greybeard ive been using same spring compresser for many years on cars and bikes , a very good tool to have , I once lent it out and forgot who had it, I got it back about a year later after knocking on many doors to find it

[bikerbob]

Read somewhere a while ago that Hepolite has been taken over by Wassell and the pistons they supply are JCC pistons made in Taiwan can anyone confirm this.

[duTch]

 

...I went to the pub at 2-30pm and fell through the door at 1am [*** ed]I am ill! yes in the head......

 You did ok then- considering

 

« Reply #70 on: May 27, 2018, 02:45:16 »

    Quote

Quote from: Morris

    I always understood that the speed of the burnt gases leaving the cylinder helps sucking in the fresh mixture, hence the overlap. This would mean though that the overall fuel consumption will rise if there’s more overlap.
    I also wonder if the carb would need to be jetted differently?


There’s more to long duration cams than the overlap (period when both valves are open, although yes, the inertia of the departing exhaust charge reduces pressure in the combustion chamber and starts to draw the fresh charge in. Overlap also allows some of the more complicated sonic effects of a tuned exhaust.

Early opening of the inlet valve before TDC means it’s already open by a useful amount when the piston starts to descend.  Late closing of the inlet valve after BDC allows the inertia of the incoming charge to cause cylinder filling to continue after the compression stroke has started.  This effect needs a few 1000s of rpm to work: at idle and low rpm, late closing of the inlet has the ill-effect of allowing mixture to be pushed back out through the inlet ports and carburettor. Mixture being blown out through the carb and then sucked back in causes richness that fouls plugs in traffic jams.

Early opening of the exhaust valve before BDC on the power stroke lets the gases start to be expelled by their own expansion pressure, at a time when they won’t do much more useful work pushing the piston down.

Are we back where we started?   

 That could explain why mine is a bit fumey around town and may explain higher consumption ratio....