Engine build prep (2014)

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lcrken said:
Fast Eddie said:
JS Carrillo conrods vs stock, the carrillos are simply things of beauty! Overall they are slightly heavier than stock (only slightly), but the little end is lighter.
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The bike is looking great, and should be really impressive when finished.

Please don't take this as a criticism, but I just noticed what you said in the original post about the weights of the rods, and thought I ought to correct it.

The small end on Jim's Carrillo rods is not lighter than the small end of stock rods. It is significantly lighter than the standard (steel) Carrillo Norton rod small end, but not than that of the stock aluminum rod. The small end weight of Jim's rods is 105 grams, where a standard Carrillo is more like 135 grams, but the small end of the stock rod is only 75 grams or so (75 - 78 on the ones I've measured). FWIW, the only aftermarket aluminum rods for Nortons that I've measured (from Kenny Dreer) were slightly heavier at the small end than Jim's, at 110 grams. Jim's setup gets it's lighter reciprocating weight from a lighter piston and lighter pin, not from the rod.

On total rod weight, the Carrillo rods, both Jim's and the standard Carrillos are heavier than the stock rod. A stock 750 rod weights around 390 grams, Jim's Carrillos weigh 431 grams, and a current standard Carrillo steel rod weighs 472 grams (earlier ones weighed as much as 512 grams). The additional weight is mostly in the big end, which is rotating weight, and doesn't affect vibration much, so I don't consider the total weight differences to be very significant.

None of this is a criticism of Jim's kit. He never claimed his rod small end was lighter than the stock rod, just lighter than the standard Carrillo and some aftermarket aluminum rods. He worked pretty hard to convince the Carrillo engineers that it was safe to make the small end that light, and the rod is indeed a thing of beauty. I've seen titanium rods for Commandos that were heavier at the small end than Jim's.

Ken
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Hi Ken

''The additional weight is mostly in the big end, which is rotating weight and doesn' t affect vibration much..."
Isn't the additional weight mostly in the small end and should be considered reciprocating weight?
If the stock small end is 35 grams lighter than the JS, then that is 35/41 or eighty five percent of the total weight difference between stock and JS rods.

Glen
 
Glen, I probably could have phrased that better. I was trying to make the point about big end weight not being very significant because it's rotating weight, but that's not how it came out. Sorry for any confusion. As you point out, the difference in small end weight is quite a bit of the difference in total rod weight, but JIm makes up for it with the lighter piston and pin assembly. A longer stock rod would be ideal, except for the fact that they eventually fatigue and develop cracks, which the steel rods don't.

Ken
 
Thanks Ken.
Sorry to nitpick, but as you can tell, I always read your posts carefully because they are filled with great info.

Glen
 
Gents,
Due to holidays and work, I've not progressed much in the last few weeks, but I hope to get some shed time in this weekend at least. And hopefully I can progress with the top end build as I've got my bits back from Camcoat, they ceramic thermal barrier coated the combustion chambers, piston crowns, valve faces, and inside of exhaust ports. Plus they've Teflon anti friction coated the Piston skirts and valve stems. Nice job they've done And very reasonable prices too.I know this may not be strictly necessary on a road engine, but I am gonna be running it at slightly over 10:1 CR and this will help protect against excess heat. Heres some pics:
Engine build prep (2014)


Engine build prep (2014)


Engine build prep (2014)


Engine build prep (2014)


Engine build prep (2014)
 
Various coatings are another nice fast way to spend money to go fast further. Peel 920 bores are off to Bore Tech for carbide bore burnishing, ugh along with my lawnmower boxer bores. Pay less now or may pay more later, i found out hard on bores the hard way on the mower cast iron light rehoned bores. So instead of racing deer across low grass I am racing grass growth before so tall just falls over.
 
hobot said:
Various coatings are another nice fast way to spend money to go fast further. Peel 920 bores are off to Bore Tech for carbide bore burnishing, ugh along with my lawnmower boxer bores. Pay less now or may pay more later, i found out hard on bores the hard way on the mower cast iron light rehoned bores. So instead of racing deer across low grass I am racing grass growth before so tall just falls over.
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I was quite surprised Hobot that some of the coating processes are not as expensive as Might be expected. Of course, if you did everything on offer for every component you spend a pretty pile, but sensible selection can get some good applications at reasonable costs.
The package of coatings I've had done on this Commando I have done on a few bikes in the past, I first got into it when racing and found it a huge saviour, curing overheating issues, stopping troublesome bikes seizing, etc, etc.
Like using good oil, I also look at it as a kind of insurance policy, a bit more protection should something be not quite right.
At the end of the day, the Commando design started out as a low compression 500cc engine... mine is an 850 high compression with not that much more fin area than the 500! So preventing heat being absorbed into the motor, and throwing it out of the exhaust instead, seems like a mighty fine idea to me!
 
Ugh picking which coating to pass up is beyond me so picking em all for Peel. Great times pushing as much heat though your hot rod 850 a long time. I've some question about polishing piston crowns which makes surface and IR photon reflector too but then don't know it the ceramic installation coat would stick. Do expect the side of pistons to rub off various coatings after a while but hope that interval was memorable worth while. Eventually we will mainly be spending on new tires and rally and track trips, won't we?
 
I know I'm off topic re 'engine' again, but following on from recent discussions, here's a pic of the Falcon shocks in situ. I'm very impressed with the look and feel of them, very good quality and VERY light. But, of course, I haven't tested them yet!

Engine build prep (2014)
 
Well, I managed to get some decent shed time in this weekend, so even at my very non-rapid pace of work, I managed to make some decent progress:

Head assembled with the JS beehive springs, although I had the rockers lightened and polished by Pete Lovell, I thought he left a tad too much metal on the extremities, so took a little more off:

Engine build prep (2014)


What do you guys do when fitting the barrels? The JS pistons are too short to allow use of a normal ring clamp whilst supporting base of pistons, and the 'gapless rings' are a bit of a fiddle, so I elected to fit them with the engine on its side, it worked a treat:

Engine build prep (2014)


JS pushrods and AN head gasket:

Engine build prep (2014)


Engine nailed together, I decided to build it on the bench and fit as a complete unit, against the advice of the shop manual:

Engine build prep (2014)


Fitting the engine as a complete unit went easier than I'd expected, the engine isn't as heavy as I thought it would be (a lot lighter than a Nourish engine for example... unless I'm stronger than I was!) here it is in situ:

Engine build prep (2014)


And again, I'm very pleased so far, I know its heresy, but I do like the silver painted barrels (my wife's idea):

Engine build prep (2014)


It's gonna be at least 3 weeks till I get my wheels back, but there's still PLENTY to be getting on with. My target of being on the road by June (meaning THIS June) is looking like it might be a challenge...
 
That is starting to look very nice indeed!

Silver 850 barrels are 'correct' for some models, so no cause for objection from the concours police ;)

Glad you're pleased with the service from Falcon - I'd heard good things from some of the Manx racer brigade, who seem to favour them.
 
Beautiful work there.

My concern is what made you go for a composite head gasket?

Those silver barrels will help you see leaks better.

I'm sorry, please don't take me too seriously.
 
pete.v said:
Beautiful work there.

My concern is what made you go for a composite head gasket?

Those silver barrels will help you see leaks better.

I'm sorry, please don't take me too seriously.
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Well, I initially favoured copper, as that's what I'm more familiar with. But consensus seemed to be to go for composite. Tony Smith told me he'd never use anything else, thats what he used when racing and thats what he uses today. That would have been enough for me, and then when I stripped the bike, it had a composite gasket that was stuck like the proverbial, and was oil tight. So that swung it for me!

Time will tell I guess!
 
Looms great. IVe just fittend my JS pistons with ring clamps, they just fittend when I supporter the pistons om the skirts. Did you check the inleg cam lobe and was iT anywhere near the 102? Mine was on 106.
Dan
 
I've read all the posts on this topic and I love what you are doing, Eddie. To my mind the most important thing is that you have the JS rods, pistons, gudgeons etc. Of all the available hot-up stuff that is the best buy. I have strong doubts about fitting really hot cams into commando motors. I look at the crankshaft, and immediately think of a billet crank. I look at the cases and immediately think of the thick wall Maney cases. In the end I believe I would end up with a really fast top end motor which would be probably more difficult to use. I've looked at a lot of the videos of Kenny Cummins racing and they are extremely impressive. However our Australian race circuits appear to often have more tight sections on them. A super-fast top end motor can often dictate that the bike needs a wide smooth line out of corners, stand up then give it the big squirt. OK for big circuits, not so good for tight ones. So my approach has always been minimalist - as cheap as possible to stay together and do the job. Torque is at a premium for me.
I'm a bit surprised that you are doing this stuff to a road bike. It is good, however expensive for something which is always going to be balked and subject to speed laws. I'd like to own your bike, however I wouldn't have my licence for long.
 
acotrel said:
I've read all the posts on this topic and I love what you are doing, Eddie. To my mind the most important thing is that you have the JS rods, pistons, gudgeons etc. Of all the available hot-up stuff that is the best buy. I have strong doubts about fitting really hot cams into commando motors. I look at the crankshaft, and immediately think of a billet crank. I look at the cases and immediately think of the thick wall Maney cases. In the end I believe I would end up with a really fast top end motor which would be probably more difficult to use. I've looked at a lot of the videos of Kenny Cummins racing and they are extremely impressive. However our Australian race circuits appear to often have more tight sections on them. A super-fast top end motor can often dictate that the bike needs a wide smooth line out of corners, stand up then give it the big squirt. OK for big circuits, not so good for tight ones. So my approach has always been minimalist - as cheap as possible to stay together and do the job. Torque is at a premium for me.
I'm a bit surprised that you are doing this stuff to a road bike. It is good, however expensive for something which is always going to be balked and subject to speed laws. I'd like to own your bike, however I wouldn't have my licence for long.
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Glad you like it Acotrel. You'll notice that I've gone for the stage 1 cam, I wanted to go for more, but went with the more knowledgable opinions! This cam is pretty similar to the BSA/ Triumph Spitfire profile I think, I chose it to give the best power between 3 and 7k rpm. Yes it's a road bike, also to be used on the track. I'm building it to turn from roadster to cafe racer very quickly! Anyway, believe it or not, some folk do break speed limits! Although I consider my Commando to be something of a hot rod, in the scheme of things, its just a slow old bike!
 
Eddie, regards the composite gasket- my Commando came with a leaking copper headgasket. I installed a new copper gas which held for a couple of weeks then started leaking. Annealed and re-installed, same problem. Tried another new copper gasket, no luck. Finally I fitted a flame ring composite gasket, problem solved so far, (5,000 miles)

Glen
 
Flamering of good quality are the cat's meow but those of low foil metal quality may not last a dozen miles blowing out the weal oil drain area with foil rim parting there. Btw for those stuffy T-wrench only-ever users, better investigate the data on temperature of parts and assembly room air to fudge your factors any better than just feel or measure stretch where possible.
 
Fast Eddie said:
Well, I managed to get some decent shed time in this weekend, so even at my very non-rapid pace of work, I managed to make some decent progress:

Engine build prep (2014)


It's gonna be at least 3 weeks till I get my wheels back, but there's still PLENTY to be getting on with. My target of being on the road by June (meaning THIS June) is looking like it might be a challenge...
Click to expand...

Obviously your keen to get it going, cos the seat is already on..., Got any wheels?? :lol: :lol: :lol: :lol: :lol: :lol:
 
olChris said:
Fast Eddie said:
Well, I managed to get some decent shed time in this weekend, so even at my very non-rapid pace of work, I managed to make some decent progress:

Engine build prep (2014)


It's gonna be at least 3 weeks till I get my wheels back, but there's still PLENTY to be getting on with. My target of being on the road by June (meaning THIS June) is looking like it might be a challenge...
Click to expand...

Obviously your keen to get it going, cos the seat is already on..., Got any wheels?? :lol: :lol: :lol: :lol: :lol: :lol:
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Don't mention the Wheels!!

At least with the seat fitted, I can sit on it and make "Brum - Brum" noises. Better than nothing I guess!!
 
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