Alp Sungurtekin 666 Vincent Speedweek SCTA BNI August 8-14, 2020

timetraveller

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Is it possible for someone to show a picture of how Alp sits on the bike, dangles off the side or whatever. An earlier picture of what seemed to be the complete bike did not illustrate where the rider would fit, or if it did I did not understand it.
 

davidd

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At present, there are no photos of anyone posted. It is early.

Alp is trying to get some time on the bike. Checking that everything is working and that the handling is OK. There is a lot to get used to.

This earlier photo shows the position that he is attempting to achieve:

Alp Sungertekin 23.png


The helmet on the left side to keep it low, the body line is flat from front to back. No instruments. This keeps the CD as low as possible on a naked bike.

David
 

Spqreddie

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On the later Norton Commando (and now common practice when earlier engines are rebuilt), "superblended" (chamfered) roller bearings are used to avoid the pitting (and eventually breaking) of the main shaft and to avoid the driving out/skrewing out of the bearing outer race. This is due to the relatively long unsupported crankshaft of the Norton that under the power of the latest, or modified, engine can flex. Can a similar bearing be used in the Vincent engine to avoid the roller bearing outer race being driven out and distort the crankshaft bore? excuse my question, may be is already a "superblended" that is used there, but i am not yet there in my Rapide rebuild, so i dont know!
Good luck to Alp, and looking forward to have more information on how his week went!
Eddie
 

davidd

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In an effort to keep the information in one place, this is a post from Bill Cannon's "Leak Down Test" thread and a question about Alp's head work:
davidd said:
Bill,

You don't need the lockring. You can bore out the threads and make the guide to fit. As long as the interference fit on the whole guide is fine, they work fine. They were like this on the big port head also. The prewar aluminum heads had lots of problems holding their shape.

David
Was it a photo of one of Alp’s heads I saw recently where he just used the interference fit? Can’t recall where I saw it though.

Cyborg

I believe that Alp had damage to at least one guide where the valve bend, split the guide, broke off the valve head and destroyed the seat. Thus, the guide hole was enlarged and a new guide with no lockring was installed.

Head Repair  (11).jpg


David
 

Monkeypants

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Here's what I have learned about Superblends.
1. Superblend is a marketing term Norton came up with when they went to the (e) designation bearing to solve main bearing failures that occured with the Combat engine. Bearing manufacturers don't know the term
2. The barrel shaped roller idea is a bit of an urban myth.
3. The E designation stands for extreme service. These bearings are rated for a higher shock load than the same size bearing without the E designation.
4. The bearing change at Norton did seem to solve the problem of mainbearing failure. They also made other changes at the same time, ( stronger cases, stronger crank, bigger engine, lower compression) so it's hard to know what exactly happened there.
I was able to get e spec bearings in the 30x72 mm size, not sure if they are available in standard Vincent size.

From reading about Picador testing, the crank issues were with mainshaft failure, big end failure and flywheels coming loose, walking out of alignment.
The problems were solved with the Picador crank which used special mainbearings that had standard OD but ID enlarged to 1 1/8" for the oversized Picador crank mainshafts. It also had a non serviceable crankpin that had a full press fit, no nuts used. The pin also went all the way through the flywheels at full diameter, it wasn't shouldered down.
This gave a much greater connection area, maybe three or four times as much as the standard crankpin to flywheel connection.
It was also at a higher interfence fit than the motorcycle engine version.
Those were referred to as a five ton fit ( hydraulic press reading) while the Picador crankpin to flywheel was at ten tons or more.
This setup was tested to 115 HP on a Supercharged engine and survived.
It also survived a continuous 65 bhp for 12 hrs as needed for the Picador engine.
Standard cranks came apart in as little as 15- 20 minutes at 48 bhp as produced by the Shadow engines ( not 55 as advertised in Brochures!)

Jim Comstock plotted the shape of a new "Superblend" roller bearing and found it to be the same as any standard roller bearing.
He had to destroy a new bearing to make the video. Kind of a waste but he wanted to know if there really was this shape difference as is so widely believed.

 
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davidd

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Alp called me today and said that everything with the engine went very well. The rear wheel (not Vincent) had a bearing seize on the axle, which required a trip to Salt Lake City to press it off, clean it up and get a new bearing.

The Morris Magneto got poor treatment by the postal service but showed up just prior to traveling to Utah.
It was an excellent job by Dave Shaw at Morris and worked perfectly. Started easily and ran well.

All of the runs involved testing, so nothing too lean or too fast. The 134 MPH run was done in third gear. The fuel was mostly alcohol, but the bike seemed to do well on some Nitro, also. The engine was run up to 8,000 and seemed quite happy.

The engine will be disassembled and checked for any problems. Everything will get back together for the next test date sometime in October at the World Finals. Vincent owner James Salter provided great assistance to Alp through the entire event!

David
 

oexing

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The so-called superblends are standard roller bearings from mid-eighties, at least for FAG and SKF types. Zoom in on my photo and see the "polished down " ends of rollers of the bearings that go in my two B engines. This roller type is called a logarithmic shape for reducing high edge loads in certain conditions. Real barrel roller bearings were used in "sports" types of Earles fork BMWs R 50 S and R 69 S , 500 cc 35 hp @7500 rpm resp. 600 cc 42 Hp @7000 rpm. Touring types had ball bearings rear and front 35x72x17mm plus one small front ball bearing behind the crank mounted generator. So three bearings on the short flat twin crank - and I still don´t quite see what the barrel roller bearing does at the rear end just next to the TAPER mounted flywheel. They felt this was a brilliant idea . . . . Note the 35 mm main shafts on the sleek BMW cranks and their "sporty" conrods, knife cross section from mid fifties on these. The later /5 series were basically very close to car engine designs for cheap production ways - extremely different beasts they were so nothing that could possibly fascinate me with my tech mind on nice engineering.
Sorry , Bruce, for being so late in sending some more photos of real classy BMWs and parts to compare to more modern Berlin Motoren Werke.

Vic

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