What did you do with your P11 today. he he

Schwany · Aug 25, 2025

Well, the excitement never ends. No I haven't blown the latest iteration of the engine up yet.

Today I lowered the suspension 1/4" all the way around and cut 1/4" off my kick stand. My suspension and kick stand are not Norton parts if you are trying to figure out how any of that is possible. I bought longer than typical length CRS forks, use Betor yokes that let me slide the 35mm stanchions up or down, and my CRS shocks can be adjusted for length. No changing preload or shortening springs or any other nonsense.

Speaking of the latest engine configuration. I might be close to 10:5:1 on the compression this time. There is a lot of piston in the squish, but no valve collision in the valve pockets. I literally can't kick the engine over fast enough to start the engine if it is at TDC. I would have to jump off a diving board to do it. Some of you beer bellied big guys might be able to do it, but it is harder than it has ever been for me in the past. Emergency random kick starts required if stalled in traffic would be very embarrassing. Maybe I just got a tight seal on the head this time and I've been a weakling all along.

Schwany · Aug 27, 2025

Today I hand filed little tapered troughs half way across the part of JSM rocker spindle covers that keep the spindle from turning and align it with the oil holes in the head for the spindles. The troughs allow more oil to pass into the exhaust spindles. You would have to have the JSM rocker spindle covers to know what I am talking about.

I adjusted the valves yesterday to the .008" intake and .010" exhaust spec for a Combat engine. I started with a .011 lash on both for the first two test rides. I also checked the timing for the 4th time to be sure the rotor wasn't moving. Anywho, I must have done something right cuz it halls the mail for an old 750 twin everywhere in the power band as long as I am in the right gear. I think the mild 2 degree cam advance timing bump took away some of the lack luster low end people whine about with the SS cam. Well that and all the other stuff I've done to the engine isn't slowing it down.

It's working well. Better than I thought it would. The SS cam definitely comes on harder than the JS2 cam. It's probably much harder on the valve train though. The compression, cam, carburetion, timing, and exhaust are getting along. Maybe I'm done.

gpzkat · Aug 30, 2025

Should this be "What did you do to your P11, N15CS, G15CS, or Atlas today?" Feeling left out

but I'll carry on as if my N15CS is a P11.

I got a 'gen-u-wine' Mikuni Viton rubber-tipped float needle assembly for my VM34, and it stopped the confounded dripping if I forget to turn the tap off.

Tomorrow I will install a new clutch nut w/seal. I had one on before, but broke it. How? That is a sordid story of idiocy I don't want to go into. Anyway, I have fresh ATF (umm, a 45-year-old can that was never opened), a new primary cover gasket, and I will do my best to get it sealed up. Last time I didn't remove my footpeg brackets, and I tore the gasket due to the contorted installation approach. Leak city. I have a plan to seal it up well, here's hoping.

Oh, when I built the bike, I got a new single-row primary chain and engine sprocket. I feared that the chain adjustment, which is a pain, would be frequent. Nope. Granted I have only 1,500 miles on the bike, but I've had the primary cover off to fix a slipping clutch at around 700 miles, and it was perfect. Since then, I have checked the ATF level a couple of times (given that it leaks...) and checked the chain through the inspection cap - there doesn't seem to be any stretching going on. Honestly this bike's as reliable as any bike I've ever had, including dozens of Japanese and a few German, Italian, Austrian, other Brits from 1950 onward.

gpzkat · Aug 31, 2025

gpzkat said:
Should this be "What did you do to your P11, N15CS, G15CS, or Atlas today?" Feeling left out but I'll carry on as if my N15CS is a P11.

Ooops, so sorry/not sorry - changing to "What did you do to your KTM" now..... I just scored a great deal ( $50 ! ) on a pair of new take-off Continental 50/50 'Twinduro' tires for the '03 KTM 450 EXC. They have 10 miles on them, date codes Oct/Dec '22. They have been inside; the rubber is nice and pliable. Can't wait to try on the road and trails. It's over 90°F today, so I'll wait until later this evening or early tomorrow to mount and balance them.

Norton content... I think these or the Shinko 'Big Block', which are similar (I put on my '23 Ducati DesertX before I sold it, and rode a few hundred miles on them) would work quite well on the P11 or N15. They have surprisingly good manners on dirt and the street, IMO amazingly so. And they come in the right sizes. The K70s I'm running are fairly short on grip, and follow rain grooves on the freeway, so it's a bit wiggly when I occasionally hit the superslab. I can live with them, but being able to lock the front at 50 MPH on dry pavement is a mixed blessing, brakes outshining the tires.

What did you do with your P11 today. he he

Schwany · Aug 31, 2025

gpzkat said:
Ooops, so sorry/not sorry - changing to "What did you do to your KTM" now..... I just scored a great deal ( $50 ! ) on a pair of new take-off Continental 50/50 'Twinduro' tires for the '03 KTM 450 EXC. They have 10 miles on them, date codes Oct/Dec '22. They have been inside; the rubber is nice and pliable. Can't wait to try on the road and trails. It's over 90°F today, so I'll wait until later this evening or early tomorrow to mount and balance them.

Norton content... I think these or the Shinko 'Big Block', which are similar (I put on my '23 Ducati DesertX before I sold it, and rode a few hundred miles on them) would work quite well on the P11 or N15. They have surprisingly good manners on dirt and the street, IMO amazingly so. And they come in the right sizes. The K70s I'm running are fairly short on grip, and follow rain grooves on the freeway, so it's a bit wiggly when I occasionally hit the superslab. I can live with them, but being able to lock the front at 50 MPH on dry pavement is a mixed blessing, brakes outshining the tires.

$50 is like free for a pair of new tires. Well done.

All things considered my P11 is not really a P11 desert sled or dual sport. I have a smidgeon of regret about not turning it into a dirt bike, but it is a kick in the foothills on winding paved roads the way I have it setup.

(Insert dirt bikes I had street licensed for dual sport I've owned here.) I never used big block knobby tires on the 4 stroke thumpers for dual sport. I did a couple of 500 mile dual sport events on my KTM 360 and it did have knobby tires on it. It however was not licensed for street use and those rides were mostly in the Nevada desert and Sierra Nevada. With very short sections of paved road.

I cheaped out and have a BT46 on the rear of the P11 and it makes the ride very interesting when going over bridges with a surface made entirely of metal grid work. First time I went over one was an eye opener. Like riding a bowl of Jello. Otherwise it's OK. I won't be buying another one though. I can't remember what it does over rain grooves. Maybe nothing weird.

I'm not sure if I'm on topic or not. Too much blood in my alcohol stream.

gpzkat · Aug 31, 2025

Hey no worries. Enjoy that snifter of brandy

That KTM has over 50HP, a 6-speed, weighs about 250lbs and will cruise at 75. I hit a 5 gallon bucket-sized pothole at 40MPH, off camber and the bike nearly tossed me, but I carried on. Lesson: Shade makes the 'road' hard to see. Shade is from foliage, foliage is from a stream. Water makes road ruts. Big ones. I don't want to eat S at my age, so I'll slow down, I promise.

The KTM has a1 liter (litre?) oil capacity and an engine lifespan measured in hours. But that's per the factory as a race bike. Many have reported a good long >20K mile life, just change oil often and use the good stuff. I am using it as an exercise device. I get 3 hours of full-body workout for less than $8 of fuel.

I have run BT46s. Way back in the 80s, as a young buck, I rode 1160 miles from Daytona Beach, Florida to San Antonio, Texas. In one day. I remember in Houston the roads made the bike so squirrely. My buddy and I traded bikes because we both liked the other more - him on my '82 Kawasaki KZ1000J, me on his '82 Suzuki GS1100E. We went accross the 45 mile Atchafalaya Bridge in Louisiana at 125MPH .

Schwany · Sep 23, 2025

Not real exciting changes.

I tapped and threaded the swing arm spindle nuts on both sides for set screws. Keeps the spindle from walking to one side or the other as well as keeping the nuts from ever coming off.

Few years ago I drilled through the nut and rear axel for a clip on the drive side. The clip keeps the nut from getting loose and the axle tight enough without a massive amount of torque.

Schwany · Sep 24, 2025

Changing fork oil in my CRS Ceriani Replica GP35 forks today. Last oil change I put some 5wt in there to sort of break them in more for the street. I'll put in some 10wt which is what CRS recommends. Maybe get in a test ride tomorrow. I've had a few different weight fork oils in there. As with everything I do with the Norton P11, it is a work in progress.

Cap with preload adjuster, spring spacer cup, 3" spacer fits into the bottom of the cup and the spacer sits on top of the spring. Thing in background in the Rebound damping adjuster. In the pic above it is the lower adjuster with the black cover. The top one is Compression damping. Brake is a 230mm CRS 4LS.

I've never had RoadHolders on the P11. Forks were gone when I got the P11 in milk crates. I put Betors on it initially. Still use the Betor yokes for the Ceriani Replicas.

gpzkat · Sep 24, 2025

Schwany said:
Changing fork oil in my CRS Ceriani Replica GP35 forks today. Last oil change I put some 5wt in there to sort of break them in more for the street. I'll put in some 10wt which is what CRS recommends. Maybe get in a test ride tomorrow. I've had a few different weight fork oils in there. As with everything I do with the Norton P11, it is a work in progress.

Cap with preload adjuster, spring spacer cup, 3" spacer fits into the bottom of the cup and the spacer sits on top of the spring. Thing in background in the Rebound damping adjuster. In the pic above it is the lower adjuster with the black cover. The top one is Compression damping. Brake is a 230mm CRS 4LS.

I've never had RoadHolders on the P11. Forks were gone when I got the P11 in milk crates. I put Betors on it initially. Still use the Betor yokes for the Ceriani Replicas.

Didn't the P11 use the Matchless Teledraulics? That's what my parts book 66-68 says.

Schwany · Sep 24, 2025

gpzkat said:
Didn't the P11 use the Matchless Teledraulics? That's what my parts book 66-68 says.

Heck if I know.

I pulled the RoadHolder name out of my ass. Restoring a P11 was not on my mind back in the early 70's or now actually.

I'm probably missing out on a softer ride, but this beast of mine is more of a road race setup and these CRS forks work really well if hard on the gas keeping the front end a little light over the bumps. Going slow and droning near the speed limit on the HWY is a bone shaker though. Hoping to correct that with this next oil change. A man can dream...

gpzkat · Sep 24, 2025

Schwany said:
Heck if I know. I pulled the RoadHolder name out of my ass. Restoring a P11 was not on my mind back in the early 70's or now actually.

I'm probably missing out on a softer ride, but this beast of mine is more of a road race setup and these CRS forks work really well if hard on the gas keeping the front end a little light over the bump. Going slow and droning near the speed limit on the HWY is a bone shaker though. Hoping to correct that with this next oil change. A man can dream...

They certainly look good!

Schwany · Sep 25, 2025

gpzkat said:
They certainly look good!

I might have made some progress on the forks with this last oil change. I reduced the amount of oil in each leg by 20cc, and used Maxima V-Twin 10wt fork oil. The reduction in oil is within the spec range. I also increased the preload a little. A ride will tell if it's a real improvement, but pumping the front end in the garage feels smoother. Not quite Ohlins smooth, but good for these forks.

Sure like the detailing you did with the old Suzuki 1100's. They are beauties.

o0norton0o · Sep 25, 2025

There's a lot going on in modern fork suspension. I've been reading "Racetech's Suspension Bible" and learned a lot of stuff that is not widely known. A few of the most interesting things are how important spring choice is since it's a fixed element, a pain to change, and also kind of expensive. Another was how the "Air spring effect" can be adjusted by changing the amount of fork oil you use. I never thought about it until I read about it, and it's a noticeable thing. I have modern adjustable showa damper sets with 51lb/in, 43lb/in, and 34lb/in springs and have tested them with 2.5, 5, and 7.5wt silkolene RSF.

Right now I am running the 34lb/in dampers with 7.5wt fork oil. They aren't as confidence inspiring as the stiffer spring sets, but they are a bit less harsh. I really like the feel of the stiffer sprung forks, but the book says that the best feel is close to, but not actually the best traction and give a graph of it too. (I think it's like the old race car idea of a tight car feeling like it has the best control, but if the driver can adjust to a looser car, it actually performs better)

Schwany · Sep 25, 2025

o0norton0o said:
There's a lot going on in modern fork suspension.

Yes there is a lot to tuning forks, which is why I lowered the amount of fork oil I'm using. I knew too much oil was contributing to the harsher ride.

RaceTech gizmos are not something I would use in these forks. I tried their Gold Valves in my Betor forks. The Gold Valves didn't improve anything significant enough for me to use any of their other valve products. I did get springs from them. Closet I could get to 40lb that would fit inside my stanchions and are not too long. 45lb. They are progressive wound. CRS springs are straight rate springs, but they went out of business before I got around to getting a set of 40lb springs, which might have been a sweet spot. Racetech at the time I wanted a spring change did not have any 40lb springs that would fit the CRS GP35 forks.

I have to take it for a ride, but I'm doing some work in my driveway that is taking up time.

gpzkat · Sep 25, 2025

I have RaceTech emulators and Sonic springs in one of my GS's. They originally had air pressure with a crossover pipe, but those holes are JB welded shut now. It was an 80s gimmick. I have found they are very sensitive to the oil level, too high gives air spring effect. I got the emulators with one of the (free) bikes, not sure I'm a fan, but probably just haven't got the whole setup dialed in yet. It's OK for normal riding, but big bump impact is too much of a jolt.

If I ever had a motorcycle with 1/2 the awesomemess of my moutain bike's mid-grade Rox Shock I'd be ecstatic. I can ride over insane stuff, the local 'rock garden' really opened my eyes to how good they are... check this out for fun. My son goes about this fast. I lag way behind but make it through.

o0norton0o · Sep 25, 2025

Racetech's emulators are high quality. I don't think having the highest quality secondary valves are all that important on a road bike. I have 2 damper sets with the honda valves which are 4 port valves and one damper set that has 3 port suzuki valves which are similar to the racetech's valve shape. I don't notice any difference in the high speed damping...

Having adjustable low speed damping and shim stack secondary valves is light years better than anything else I've tried in a Norton commando for public roads...

Schwany · Sep 26, 2025

o0norton0o said:
Racetech's emulators are high quality. I don't think having the highest quality secondary valves are all that important on a road bike. I have 2 damper sets with the honda valves which are 4 port valves and one damper set that has 3 port suzuki valves which are similar to the racetech's valve shape. I don't notice any difference in the high speed damping...

Having adjustable low speed damping and shim stack secondary valves is light years better than anything else I've tried in a Norton commando for public roads...

You want light years better, get you some Ohlins forks. Unfortunately, the Norton Commando was never on the Ohlins give a darn list. No bolt on kits like they have for Ducati and other high performance motorcycles. Their bolt on stuff works.

Schwany · Sep 27, 2025

gpzkat said:
I have RaceTech emulators and Sonic springs in one of my GS's. They originally had air pressure with a crossover pipe, but those holes are JB welded shut now. It was an 80s gimmick. I have found they are very sensitive to the oil level, too high gives air spring effect. I got the emulators with one of the (free) bikes, not sure I'm a fan, but probably just haven't got the whole setup dialed in yet. It's OK for normal riding, but big bump impact is too much of a jolt.

If I ever had a motorcycle with 1/2 the awesomemess of my moutain bike's mid-grade Rox Shock I'd be ecstatic. I can ride over insane stuff, the local 'rock garden' really opened my eyes to how good they are... check this out for fun. My son goes about this fast. I lag way behind but make it through.

Ouch, looks like an arm pump nightmare ride in the video. Would have been ultra nasty in the rain. I was never a huge fan of ruts, but did a few long downhills in them when I was a lot younger.

My old mountain bikes have Fox suspenders. I have not ridden off road on a mountain bike for at least 10 years. No plans to do it again.

As I mentioned, for me nothing compares to top tier Ohlins on a motorcycle. Certainly nothing Norton ever came up with in the 1970's.

Hope I get my butt out there and do a little loop that has a lot of patched pot holes soon. I think the light weight oil break in theory helped with the CRS GP35 forks, and now the lower capacity with 10wt is in the sweet spot for being able to make adjustments for road and track. Not that I will ever get on a track. Too many hoops to jump through to get any track day riding.

o0norton0o · Sep 27, 2025

gpzkat said:
If I ever had a motorcycle with 1/2 the awesomemess of my moutain bike's mid-grade Rox Shock I'd be ecstatic. I can ride over insane stuff, the local 'rock garden' really opened my eyes to how good they are... check this out for fun. My son goes about this fast. I lag way behind but make it through.

You also have to remember that the primary goal of forks on a road bike is to maintain traction, where as with a dirt bike, it isn't trying to maximize traction as much as control the effects of impacting terrain irregularities to maintain the stability and attitude of the chassis. So dirt bike suspension or mountain bike suspension isn't designed to have the same focus as road going suspension. Your Fox mountain bike suspension would be buttery smooth to use on a road bike, but the bike would suck at maintaining traction and handling compared to modern road bike suspension.

When I was doing my damper project testing, I did a side by side swap on norton commandos. My friend had pretty new stock suspension and my bike had modified modern showa 20mm dampers with adjustable low speed damping and shim stack valve secondaries. His bike floated down the road on a cloud, but felt less precise in it's steering and not as confidence inspiring when laying it into a corner. My bike felt exactly opposite, crisp steering and control, with predictable confidence inspring handling, BUT it certainly didn't ride on a cloud like his bike did. Eventually, I made my friend a set of modern damper inserts for his own bike and he loves the improvement in handling, even with the loss of that floating on a cloud feel of the soft suspension he had with the stock parts.... That was the surprise (to me) conclusion of my project. I though I would get both a buttery smooth ride and better traction at the same time... little did I know then that those qualities are opposite ends of the same stick. The only twist to that relationship is the use of spring loaded secondary valves that kick in and out for big hits, but you never get that floating on a cloud feel that soft, underdamped suspension gives..

gpzkat · Sep 27, 2025

o0norton0o said:
You also have to remember that the primary goal of forks on a road bike is to maintain traction, where as with a dirt bike, it isn't trying to maximize traction as much as control the effects of impacting terrain irregularities to maintain the stability and attitude of the chassis. So dirt bike suspension or mountain bike suspension isn't designed to have the same focus as road going suspension. Your Fox mountain bike suspension would be buttery smooth to use on a road bike, but the bike would suck at maintaining traction and handling compared to modern road bike suspension.

When I was doing my damper project testing, I did a side by side swap on norton commandos. My friend had pretty new stock suspension and my bike had modified modern showa 20mm dampers with adjustable low speed damping and shim stack valve secondaries. His bike floated down the road on a cloud, but felt less precise in it's steering and not as confidence inspiring when laying it into a corner. My bike felt exactly opposite, crisp steering and control, with predictable confidence inspring handling, BUT it certainly didn't ride on a cloud like his bike did. Eventually, I made my friend a set of modern damper inserts for his own bike and he loves the improvement in handling, even with the loss of that floating on a cloud feel of the soft suspension he had with the stock parts.... That was the surprise (to me) conclusion of my project. I though I would get both a buttery smooth ride and better traction at the same time... little did I know then that those qualities are opposite ends of the same stick. The only twist to that relationship is the use of spring loaded secondary valves that kick in and out for big hits, but you never get that floating on a cloud feel that soft, underdamped suspension gives..

Makes sense. My son and I share bikes, and his/my '03 KTM 450 EXC is now shod with new (takeoffs) 50/50 tires, so I'm riding it a bit on the street. It pitches a lot on braking, of course. Still, I have fun on it, but keep within its limitations. The Suzuki is firm, how I like it, just that one area of impact compliance to sort out, which I'm pretty sure can be fixed with less/lighter weight oil. The Roadholders on the N15 surprised me; they do what I need for how I ride. One time off-road I hit a BIG series of potholes due to visibility/stupidability and I was quite happy with the fact that they did their job and I didn't endo the thing. I have cheap no-name shocks on the rear, not great but not bad either. I've always had a hodge-podge of bikes and 90% have been in the $0 to $1500 range, so I you know what they say about beggars and choosers.

What did you do with your P11 today. he he

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