NRE parts??? Does anyone have a contact on parts for Nourish Racing Twin engines ?

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rotorwrinch

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I have spoken with Dave N. and he is very much willing to help, but his production capabilities are limited. I will need many parts to make this work. The most difficult being a set of rocker arms. Any assistance appreciated.
 
rotorwrinch said:
I have spoken with Dave N. and he is very much willing to help, but his production capabilities are limited. I will need many parts to make this work. The most difficult being a set of rocker arms. Any assistance appreciated.
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What assistance do you need?

Ed
 
Hi Rotorwritch
What engine/Conversion?
I have a few 8 valve parts for the Triumph 650 kit. I also know a couple of racers with some spares.
I think I have a full set of tss rocker arms as well.
All the best Chris
 
Steve Campbell at Thunder Engineering in Leicester UK can help with big end shells, maybe some other Weslake /Nourish parts, but probably not rocker arms.
I wonder if TSS ones would fit ? - you might be able to find someone still with spare stock.

Duncan
 
Nourish shells are based on the Norton 1.75" journal but he did not always use Norton shells but also modified Austin Mini A series + and Triumph Dolomite Sprint big end shells. These alternative shells are wider than Norton but even if trimmed to fit a con rod with the same width as a Norton rod the bearing surface would be wider or allow use of a wider con rod for even greater bearing surface area. That plus being a lot cheaper than Norton shells due to being made in higher volumes even today would make an attractive route.

Norton big end shell width 20.3mm

Norton con-rod big end width 25.6mm

So you could go 5mm wider on the shell bearing giving a useful 25% more bearing surface area.
 
Kinda seems too obvious Kommando !

Is there a reason Norton would have specified a narrower shell ?
 
Fast Eddie said:
Kinda seems too obvious Kommando !

Is there a reason Norton would have specified a narrower shell ?
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Given Norton's propensity to continue to use older designs and save money on tooling, etc...
I wonder if, looking back, the conrod width of Model 7, (77?), 88, 99, 650's, Atlas... was similar to 20.3mm?
I realise that, from 650's on, the journal size was larger - but... who knows?

Edit: just checked a spare rod from a 650 - yep - 25.6mm - and the witness mark of the shell is a good 2mm in from the edge.
Never thought about it before!
Of course, there is the radius either side of the journal to allow for...
 
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If you look at shell bearing installations in engines it's very common to have a wide clearance at the sides of the bearing and not just a Norton thing. Not sure of the reason but the notch in both the bearing and the con rod housing have a tolerance on position and the notch in the con rod housing is wider than the notch on the bearing, so a lot of leeway in manual assembly in fast moving production for the bearing to finally sit and you don't want it sticking out of the housing. But at least for the blueprint assembly it gives potential to improve the bearing function. The other issue is the radius on the journal, this could make the 25mm width an issue as the radius is 90 thou, so 45 thou each side eg 1.1 mm.
 
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kommando said:
Nourish shells are based on the Norton 1.75" journal but he did not always use Norton shells but also modified Austin Mini A series + and Triumph Dolomite Sprint big end shells. These alternative shells are wider than Norton but even if trimmed to fit a con rod with the same width as a Norton rod the bearing surface would be wider or allow use of a wider con rod for even greater bearing surface area. That plus being a lot cheaper than Norton shells due to being made in higher volumes even today would make an attractive route.

Norton big end shell width 20.3mm

Norton con-rod big end width 25.6mm

So you could go 5mm wider on the shell bearing giving a useful 25% more bearing surface area.
Click to expand...

The journals on the last NRE crank we had were narrower than Norton ones, we had to narrow the rods to fit
 
OK, this is Dave Nourish's series of cases, matching alloy cylinder and cylinder head casting. Nothing else. If I can find components on someone's shelf, it will maybe make this project doable. If everything has to be fabbed, it will never make it on my watch. There are some Triumph patterned parts that will work. Insight and inventory prospects are what I need right now.
 
Hmmm, you‘ll need Nourish cams and crank. I think Triumph timing wheels might work and I think a Norton oil pump fits. Steve at Thunder will be able to sort rods.

I believe the TSS rockers will fit. Pushrods and tubes will be easy to knock up, Triumph cam followers will fit with slight mods.

So, it is kinda doable, but it’s a lot of work. Cams and crank are gonna be you toughest items me thinks.
 
The engine would have a target size of 750cc with allowable overbore of .060". Can anyone confirm that the NRE engines have the same bore centers as the Triumph big twins?
 
I just measured a T140 barrel and a 750 ( 73.5mm bore ) NRE barrel and the NRE has .10 inch (+/- .005?) wider bore centers.. I seem to remember that on the NRE engines the centre line of the bores was offset to the centre line of the crank journals - on the original Nourish made conrods the little end was offset to the big ends. On the Carrillos Dave subsequently provided he simply made the little ends narrower and there was no apparent offset in the con rod.
Hope this helps.
Duncan
 
Rotorwrinch
I've asked the question about spares with Gary Bryant RGB, he has some cams. Dave has brand new rockers but they are not cheap! You will need to ask Dave for the timing wheels as well. It seems little is comparable.
 
OK, info from the field is indicating that some of the components that would make a build easier will likely not be a drop in fit. Thanks for sharing the knowledge. I believe that an engine built with the NRE architecture represents a high water mark for British based racers. I do hope to find a path that will get another one to the track.
 
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