Tomorrow looks like fun

I plan to gear it for a little over 100 with the 6-speed trans. I hope that leaves me with a 1st gear still suitable for the trail.
Gear rations are below.
1st - 3.02
2nd - 2.26
3rd - 1.76
4th - 1.40
5th - 1.16
6th - 1.00
Riding the Maico or the KTM is fun but when I ride the P-11 I get all kinds of attention. Few people even know what it is, when they see how fast it is they can't believe it is 45 years old. When you hear a modern 4-stroke you can't even believe they are related. Nothing sounds as good as a Norton puffing up a hill.

Well after cooling off I retorqued the head and adjusted the valves. I pulled the carbs and changed the needles, mains and pilots. The mixture is in the ballpark now.

I warmed it up again and hit the throttle a few times. At 5500 rpm it said 75 horse. Above 5000 rpm the pull is so hard it distorts the front mount enough that the lower belt starts jumping teeth. I may have to try some extra rubbers in the mount. It vibrates pretty ferociously at that speed.

No more noise today. Jim

Is the "ferocious" vibration within the range of normal? When you say the lower belt slips are you referring to one of the dyno belts or the primary? Have you messed with the timing yet? Could that contribute to the vibration?

Looking at the movie I see it moving around quite a bit on the front isolastic mount and what appears to be a single Bolt in the rear holding everything in place with no head steady or 3rd mount to keep it from rocking or shaking. Am I mistaken in this? I know a commando will shake in the frame pretty badly without a decent top mount.

Wow, and I thought riding a 750 Triumph Metisse was fun, can't imagine this thing in the dirt, knobby one minute, slick the next. Wouldn't want to ride behind Kent, the roost will kill: rocks, knobs and tree roots.

I'm new to the site so aren't up on Norton specs but was curious as to the bore and stroke of a 1007cc Commando engine? And what would be considered max safe rpm? Thanks, Mark

kentvander said:

Is the "ferocious" vibration within the range of normal? When you say the lower belt slips are you referring to one of the dyno belts or the primary? Have you messed with the timing yet? Could that contribute to the vibration?

Looking at the movie I see it moving around quite a bit on the front isolastic mount and what appears to be a single Bolt in the rear holding everything in place with no head steady or 3rd mount to keep it from rocking or shaking. Am I mistaken in this? I know a commando will shake in the frame pretty badly without a decent top mount.

Click to expand...

It obviously hits a harmonic vibration at higher engine speeds. It really has no bearing on how it is going to vibrate once it is mounted in a solid frame. It is a product of the mounting arrangement on my dyno. Jim

marksterrtt said:

Wow, and I thought riding a 750 Triumph Metisse was fun, can't imagine this thing in the dirt, knobby one minute, slick the next. Wouldn't want to ride behind Kent, the roost will kill: rocks, knobs and tree roots.

I'm new to the site so aren't up on Norton specs but was curious as to the bore and stroke of a 1007cc Commando engine? And what would be considered max safe rpm? Thanks, Mark

Click to expand...

Yeah I have ridden a few pretty powerful dirtbikes. I even raced a KTM 495 for several years. Even then I am not so sure I would be real comfy riding this beast. It hits hard and fast.

It is a 93mm stroke and I think the bore was 83mm [without looking]. With Carrillo rods and light pistons it should be good for 6500 RPM but I figure this motor will be peaked out by 6000. Jim

Oh Man it throbs in the ribs like a living Heart Muscle! Ain't even broke in friction wise not even on the main jet yet, pity the poor tire and followers will be hurting with the Roar of a Big Heavy Twin among disposable buzz saws and ATV sounds.

Got your number down now Kent as a dirt ball G force junkie not a purified speed freak. Its excites me no end to hear how you plan make that brute earn its keep getting you off. I gave deep thought to my hi torque low rpm in bad conditions use and decided to get lowest granny creeper smoker + 3 more widest gears should do it over the speed ranges each one is appropriate for. Once ya got more torque than grip then no need to be reving in top power. I find taller gear helps hook up smoother. Nice to get into states of backing off to accelerates and nailing to slow and tossing to brake and turn. What are the type events you run with others in? What kind size make tire do ya like?
Can't wait to see what a seasoned manic dream machine will like with its lunatic.

As for isolastics too heavy, ha we shall see about that by measure and video in due time.

Don't know if ya seen this Kent but gives some hint where not to bog below 100, ground speed though tire might be.
[video]https://www.youtube.com/watch?v=fkYpWySknw8[/video]

Here's some inspirational viewing to get our juices flowing though Norotn.

[video]https://www.youtube.com/watch?feature=endscreen&v=AHY5zXP-Gs4&list=PL6DB5356E32E5B20A&NR=1[/video]

I hate it when people have to put loud music overtop the great Norton sound!
Jaydee

If the vibration is only harmonics with the dyno mounting it will be encouraging that it hopefully won't be a problem in the bike.

The Flat-Track video is particularly inspiring as I love a good feet up crossed up slide. Let off to accelerate, more throttle to turn, you bet. Stop when you feel the ground against your helmet. I have eased up a bit with age but I'll get the adrenalin flowing all the same.

My KTM has a 5.60X18 that is too big to fit on the Maico. I don't knwo if that much tire will fit on the Metisse frame or the even a custom frame if the offset of the chain is not far enough to allow it. I have a 4.50X18 on the P-11 and there is evidence of the knobs rubbing the chain.

kentvander said:

If the vibration is only harmonics with the dyno mounting it will be encouraging that it hopefully won't be a problem in the bike.

Click to expand...

It is a big 360 degree twin. It makes a lot of vibrating force. It is balanced at 72% -so 72% of the force will be on the horizontal [front to rear] plane and 28% will be vertical. Strong mounts will be necessary.

Whether it excites a harmonic in the chassis is totally a function of the chassis and mounting and the plane of vibration [balance factor]. Jim

Kent you are only one to talk dirty loose lingo on this list to me but most my riding is trying NOT to be crossed up feet on pegs staying upright sliding off into something mean. Vibration in racing ain't the same to tolerate as vibration cruising on pavement in public or race tarmac. Adrenalin covers up a good bit of vibration, for a while and off road texture mostly over whelms anyways for a while. When I kick up heels hard rock and roll starts playing in my head so appropriate in the video for my pilot sense of fun rather than spectators. i think the off roads get busted up more but less deaths and bike losses than the road racers. I like the stubby profile of the Maney block and reminds me of the new Polaris Indian engine, but only one half of course. Go tear something up for us please.

Went to the auto parts store this morning and got a couple control arm bushings to replace the iso bushings in the front mount.



Much better.

Put about 1 hr run time on the motor and then did a few WOT pulls. It easily made over 85 horse even with a mixture around 10-1 at full throttle. It also easily pulls over 6500 RPM.
I am beginning to think the engine sim software may be pretty close to right. Jim

Jim is having too much fun and chores nursing his new baby to adulthood. What CR and what cam installed and degree'd to please? I assume with the strong hi end proven components the long stroke rpm max will be the friction drop in torque/horse power rise rather than an item about fail. Could be a bullet proof engine ---> with a rev limiter installed. Kent's 6 spd offers a lot of shifting opportunity to miss one now and then. After this crankshafts dynoing a road wheel dyno seriers would narrow down the power drain factor of our type, size, lube, speed drive trains. I am more interested in the torque levels seen, please reveal when able.

Thanx for the tire sizes. I think Peel'l end up with 5x16" for some foot printing on lower pressures such as drag strip slicks and cleated hill climbs.

You know I'm going try to perfect this sort of stupidity while not being so stupid not to armor Peel for the inevitable. In a number of athletic involved sporting activities its was common to hear " Well if ya ain't falling then ya ain't really trying..."

[video]https://www.youtube.com/watch?v=mCh7fRO24VQ[/video]

If ya'll ever get to be an old men, what sort of stupidity will linger the most...
[video]https://www.youtube.com/watch?v=9I1ksEz6oSI[/video]

Comnoz, Good thinking on the bushings, I am sure they're a little stiffer than the iso bushing. Sounds like things are running strong, 85+ with a rich 10-1, some jetting and timing should get you over 90HP and that would be awesome ! are you also running race fuel? Do you know what the compression ration ended up at? Is there a minimum octane I need to shoot for. I just run premium unleaded in my other bikes. The two-strokes actually run better on premium unleaded than on race fuel. The P-11 doesn't seem to care.

Hobot, thanks for what sounded kind of like a compliment. It's too bad my ability doesn't match my confidence or ambition or I'd have been a great racer. I have put on some great shows but rarely finished 1st. I can still have fun and sometimes put on a good show. Having the wildest machines doesn't hurt.

kentvander said:

Comnoz, Good thinking on the bushings, I am sure they're a little stiffer than the iso bushing. Sounds like things are running strong, 85+ with a rich 10-1, some jetting and timing should get you over 90HP and that would be awesome ! are you also running race fuel? Do you know what the compression ration ended up at? Is there a minimum octane I need to shoot for. I just run premium unleaded in my other bikes. The two-strokes actually run better on premium unleaded than on race fuel. The P-11 doesn't seem to care.

Hobot, thanks for what sounded kind of like a compliment. It's too bad my ability doesn't match my confidence or ambition or I'd have been a great racer. I have put on some great shows but rarely finished 1st. I can still have fun and sometimes put on a good show. Having the wildest machines doesn't hurt.

Click to expand...

Kent,
I am running Sunoco 110 race fuel. The compression is around 11-1 and you will need lots of octain.

I suspect with more runtime to reduce the friction and leaner jetting the horsepower will be 95 to 100. I am pleasantly surprised.
I know the engine sim software said 98 horse but I didn't think it would do it.

Hobot,
The cam is a custom Web Cam made to my specs. Nothing too wild. Low lift but fast ramps. Jim

Jim,
When you say the head is a Fullauto, do you mean a standard spec. Or Have you modified it to suit the bigger capacity and 35mm carbs?
Martyn.

Thanx for the educational entertaining details. Online Calc's say if 95 hp @ 6800 rpm implies ~ 74 lbft tug. Confidence is a very relative feeling > instant to instant on the fly. FullAuto ports must really be moving mix fast to fill those big gups in time.

Matchless said:

Jim,
When you say the head is a Fullauto, do you mean a standard spec. Or Have you modified it to suit the bigger capacity and 35mm carbs?
Martyn.

Click to expand...

It is a fullauto head with 3mm oversize intake valves and re-angled intake guides. There are several hours worth of work done blending and matching the ports and cleaning up the area around the guides but they have not been enlarged by any more than it took to make them match.

Here is a shot of the head. You can see the larger seats have been installed and the area around the seats have been relieved for flow into the chamber. The bore has been enlarged for the big pistons and the bolt holes have been countersunk for plugs to move the bolt holes outward for the big barrels wider bolt spacing.





Here is the difference between the Maney head pattern and a stock 850 pattern.



Here is a shot after the holes were plugged and surfaced. Now just drill new holes.





The Maney barrels don't have room for an oil drainback hole so an external draintube is added.





Then it gets cc'ed and the chamber equalized at 55.5 cc's



Then it gets assembled with Black Diamond valves, JS springs and a set of custom spacers to replace the rocker springs.

So what is the cleaned up port diameter?