1961 Dominator 99 rocker oil feed

Hi Don, my reply will, no doubt, immediately be contradicted! Unless you thrash your bike for long distances, a 50 grade mono oil is probably a bit too thick. I am not going to restart the argument, about mono versus multigrade oils (although I am sticking with 20/50!). However, if you wish to use a mono oil, the correct grade (for normal road use) is:- Summer 40 S.A.E. & 30 S.A.E. when below 32 f. (probably never, in Perth!). The thinner oil will circulate more freely, and cause slightly less wear, while reaching working temperature. Making a groove in the banjo may help, but, you do not say if you mean the "take off", or the one feeding the rocker. The "T" connection to the rockers is the correct one, so the oil feed is equal on both sides. Have you tried taking off a rocker cover (when the engine is hot), to see if the rocker is running dry? I guess you are moving into summer, down there, and want to be on the road, not in the workshop!

Good luck, John.

The accepted modification used to be , fit a banjo from the 250 which has a more restricted flow to the tank and sends more to the head. I have fitted a set of six start pump gears instead which increases the flow and pressure, but some think this justs overpressurises the system and increases wear on the pump.I am of the opinion that many dommy rod failures and siezes are due to lubrication failure so i am going with the six start gears. If you go this way i would reccomend pipeing the breather into the oil tank or fit a non return breather to avoid discharge onto tyres.

Just a word of warning about the use of 6-start pumps. Never do it without the recommended Norton modification of the con-rods. Obviously this will need an engine stripdown, not just changing the pump in the timing cover.

Cheers, Lionel

Hello Yes lionel well said . its can be down to the pressure releave valve being stuck ? my friend like the low 3 start pump? And i think you sould clean all the oil ways out ? and do not forget the one at the back of the cylinder barrel?

Previously wrote:

Just a word of warning about the use of 6-start pumps. Never do it without the recommended Norton modification of the con-rods. Obviously this will need an engine stripdown, not just changing the pump in the timing cover.

Cheers, Lionel Hi Lionel, I had my doubts about fitting a set of 6 start gears ,that was 18 years ago!! , appart from a tendancy to kick out a bit more oil i have not had any problems, and have not siezed or thrown a rod ( minor irritations on an 88 i had before) , what disaster is about to befall me ?. My current motor has a well worn orriginal crank which probably flings as much oil as the rod drillings would have if i had them.

If your bike engine has the early Norton oil pump of smaller capacity then fitting the 6 speed gears should not be a problem. The oil pressure release valve will control the system pressure when the oil is cold.

However, if you have the larger capacity pump, stamped with an 'S' on the body then this item combined with 6 speedgears could cause over-oiling.

All the Norton Twin oil pumps wear more quickly on the return feed side because they spend most of their lives running on a mix of air, oil and engine waste products. Consequently, the return feed to the oil tank becomes poor and the knock-on effect of this can be less oil getting to the rockers.

Whatever oil pump you have fitted, I would recommend an inspection and service of the internals. It is quite easy to do and there are several good info sheets on this website to help with the procedure.

One suggestion to improve your rockeroil flowcould be to convert to a pressure feed from the timing cover, as most post 1966 Norton engines had. However, this may mean having to change your rocker spindles for the later type and possibly the rocker arms themselves if they are badly worn.

The suggestion of changing or altering the return feed pipe union tohelp flow distribution is also a good move but should be unnecessary if the oil pump is working well.

A lateral thinking easy bodge, I have seen, that works in a similar way to the above is to get a piece of oil proof tubing with a 3/8" internal bore. It needs to be around 4" long and cut with a lengthway slit. This is then slipped over the returnpiping inside the oil tank so that it cover the return outlet hole. When the engine is cold and first started, it helps to restrict the return flow and send lots of oil to the rockers. Many people use a finger to achieve a similar result. As the oil warms up the tubing softens, gives a littleand then allows more oil back into the tank.

I would not recommend this as a permanent fix but it solved my rocker feed problem until I was able toservice my oil pump.

Previously wrote:

Hi Phil. Thank you for your comments and suggestions. I think my problem has been traced to a 'bodged' banjo which feeds the rockers and was severely restricting the oil flow. I have replaced it with a correct one from RGM and now have good flow to the rockers. I carefully removed an end plate from a rocker while the engine was running and hot. Oil 'pulsed' out of the rocker spindle when the engine was reved. I think this is correct?

Spindles and rockers were all checked ok recently, push rods, tappets and rocker ball ends were replaced with new one at the same time. (I think all this was a result of the offending Banjo which was fitted by a previous owner/restorer. Not the only 'funnies' I have found. - may he rot in hell!!!)

Again, thanks for all the help and advice from this forum. Priceless stuff when you are a remote club member.

Dear Don,

I have a 1965 650ss that I have owned since 1976 and every timeI finish a journey I take off the oil filler cap whilst the engine is still running and put my forefinger over the return oil pipe hole in th oil tank until I hear the tappets noticeably quieten. This tells me that they are getting a surplus of oil which circulates momentarily until I stop the engine and also provides a mini reservoir of "trapped" oil until I come to start the machine again. In all this time I have never had an oil problem.

Regards,

Peter Bolton

Hi Don, Interested to hear you rode Nortons in Edinburgh 48 yrs ago. I was around at that time on a 1959 red 99 with full avonaire fairing, did our paths cross? My local bike shop was Eddie Tasker's. Bike reg. was 55ASM and my brother's was a 99 red/dove grey 1960, reg. WVA705 which I still have here in France.

Regards, Les Whyte

I bought my 99 (VBE 290) part dismantled in 1969 from a garden shed in Mayfield Road. It was well known at the University bike club (EUMCC). I even raced it at East Fortune - won £4! Eddie Tasker eventually gave up his shop and was last seen running a hardware shop in Gullane. After various travels, I am now near Biggar and so the 99 is still seen in the streets of Edinburgh from time to time. Gordon.

Previously wrote:

Hi Les. I lived in Currie and had a number of bikes from 1962 to about 1966. My first Norton was a 1955 '88' much modified and ridden into the ground. The 88 was bought at Tasker's in 1964 and sold back there in 65. Rego MVA605. Next a 1961 '99' Rego 37BVD which I bought in Glasgow and sold to Alexander's in Lothian Road, (I now have another 1961 '99'!). I don't remember many names from that time, mostly nicknames! I used to hang about at the 'Dell Cafe' in Collington and make sorties with the guys into the Pied Piper in Charlotte Street and a cafe in Pennicuik. Great to hear from you and it would be good to hear any of your memories. I live in Perth Western Australia.

All the best, Don Constable.

Hi Don and Gordon, Nice to hear from you. I believe I predate both of you as I graduated in 1962 and then did 1 year at Moray House. I started teaching in Fife and commuted either last ferry Sun evening or first Mon morning to my 'digs' in Leven returning home (Montrose Terrace) on Fri after School. I watched progress on the Road Bridge and then sold my 99 and bought a "bug-eyed" Austin Healey Sprite. I wish I had kept both!!! Previously, I lived in Paisley Crescent and our group tended to meet in Arcari's in Portobello. Sunday was the day of outings down to Gullane or Aberlady always via Luca's in Musselburgh. Unfortunately, I worked in Dan T Munro's garage on Sundays to help finance my studies and my 99 so I used to go down the coast to meet up for the return trip. Don, I have a cousin Douglas Thomson in Perth so if you come across him say hello from me. An ex colleauge also lives in Perth, Alan Meney, he is easy to find in the phone book! Again pass on my regards. Interesting the reg nos of my 99 and your machine being so close MVA605/WVA705 registered in Lanarkshire 5 year's apart.

Gordon, Eddie Tasker used to live in Penicuik when he used a Manx as road transport and last time I saw him he was in Fairmilehead. I will be in Edinburgh on 8th Feb and hope to meet up with Dougie Muir and other members of the Edin Branch of NOC on Thurs9th or Fri !)th for a hatter. May see you then. My email address is lesjea@yahoo.fr Regards, Les

Hi guys

Nice to follow all your tales and I hope your oil problem is solved Don. After Eddie sold the bike shop in Broughton Street he moved to East Lothian and ran a hardware shop in Gullane until his retirement. Following the death of his wife he moved to Millerhill near Dalkeith but sadly contracted cancer and passed away some years ago. His shop was always a great place to meet up withfriends andI have (hopefully) attached an early photo of Eddie receiving an award.

Les. Looking forward to meeting up next month.

Dougie

Hi Dougie, Thanks for the update and the photo, it takes me back a bit! I frequented Eddie's when he was in Lower London Road as I lived in Willowbrae. He latterly had a mechanic( Nebbie?) who lived I think in Portobello. Did you meet him. He also scrambled Eddie's Special a 500 Manx in a BSA frame. Eddie used to say that it was great, no maintenance as the engine ran well below its capabilities. Lift the head at the end of the season and check all was well. Hope to see you in Edinburgh.

Cheers, Les

Previously wrote:

Hi John, My mistake on the oil, I should have been more specific.The oil I use in summer here is Penrite HPR 50 which is a multigrade and is 25w-60. An excellent Australian produced oil. Normal riding conditions are over 20C and up to 35C (68f - 95f).

The 'Banjo' I modified was the one on the oil tank which feeds the pipe to the rockers. I am replacing the oil feeds to the rockers with the T arrangement.

Prior to all this the rockers did seem a bit dry. Also I have had problems with tappet wear, as stated earlier.

Thanks,

Don

Hi Don, I also use Penrite HPR 50 in my 650SS as well as my ES-2 and Ferguson Tractor. Have done now for about 25 years. It is ideally suited to Melbourne summers (up to 40 degrees Centigrade)

However, having just bought a drum last Friday I need to confirm that Penrite HPR 50 is an SAE 40:70 oil. i.e. the base oil is an SAE 40 oil which still matches the Norton manuals for summer use. (Not the 25w-60)

regards,

Ian