Hello all
Can anyone help me find a new exhaust valve for my Model 95L?
The head diameter of the one that came out is 1.625" head dia, stem 0.373 (3/8") and the length is 4.125"
The first question is - is that the correct length? I ask because after 1000 miles, the guide is so badly worn that is a wonder the bike ran at all. It was last used in anger at the 2023 Bo-Peep regularity event in Sussex and it did quite well.
I am querying the length because I am concerned that the rocker strike angle might be incorrect. I machined the guides out of a grade of cast iron that came recommended for valve guides. The inlet guide seems fine.
I have looked at the valves in the club shop but all are shorter in length. The nearest are those listed for the Model 80.
If anyone can help I would be most grateful. I am retiring this year and I am hoping to campaign the bike more often!
Rgds
Mark

Quote from: Thomas on March 05, 2024, 11:11:28 AMThe tube is just plugged into the respective hole in the head without any gasket. As I said, there is only one connection to the inlet valve in my head. The other one is dead. 

Language: Try deepl.com for translation. Helps a lot.

Have big help from Chris Odling
Good sketch for forum
In mine rokerbox felt missing 😔
Also shimming plugs. and now looking for thread size
Anyone know what's I'm needing ?
Till last year been working just with metric stuf
Bike will be on edinburgh  motorshow next week   together with my jawas 👌
Thanks for help

LOL....this is just so typical Hahaha.......this event will be a nightmare to get to being as the M25 is shut from 15th to the 18th of March for improvements junction 10 to 11......junction 10 is the turn off you need for Brooklands from the M25.....I'd normally take the clockwise M25 but reckon I'll be looking at travelling the A25 to Guildford then getting onto the A3 from there........who knows what the traffic will be like.....hopefully leave early doors 6am so should be alright

The tube is just plugged into the respective hole in the head without any gasket. As I said, there is only one connection to the inlet valve in my head. The other one is dead. 

Language: Try deepl.com for translation. Helps a lot.

Quote from: Thomas on March 03, 2024, 07:01:22 PMIn the rocker box of my Model 9 from 1937 I have an adjustment option for the inlet valve (some engines also have this for the exhaust valve). Do you have that too?

No don't have just have small bolts on both sides of the roker box try to make some photos tomorrow
Do you have photo how is the smal tube conecting to cylinder head?
Mine was damaged
Thanks

In the rocker box of my Model 9 from 1937 I have an adjustment option for the inlet valve (some engines also have this for the exhaust valve). Do you have that too?

Hi
Just starting engine after full rebuild Model 9 1936 newer hearing it before
Looks like to much oil is pumping to valve guides and leaking over head
Is any adjustment for oil flow?
Thanks for help and sorry for bad English
Greetings from Scotland

A strip of polished steel is glued to my tank. I have never seen this on any other machine. Is this original and/or what could it be for?
Thomas

Hi Russ,

you can estimate it by yourself by considering the angular connection between crank rotation and linear stroke. A full motor revolution of 360 degrees transports the piston from one TDC to the next. I set the zero point of the necessary sinus function at half stroke (49mm, 90° BTDC). That means, the crank rotation has its upper maximum (TDC) at 90°.

55° BTDC are then 35° from zero of the sinus. sin 35° is about 0.57 of the 49mm half stroke, hence at 28mm from zero. That is far away from 49mm – 14.3mm (9/16") = 34.7mm. So, either 9/16" or 55° are wrong. My 1937 Model 9 runs perfectly well with 9/16" BTDC (as given in the user manual). The upper calculation then results in 43° BTDC.

BTW: When for any reason an adjustment on the road is needed you can just take a 9/16 spanner as a measure.

Cheers, Thomas

ok chaps so I'm after ignition timing  for my 1927 model 9 I've seen the chart here and know it's 55 deg's BTDC but does anyone know what that is in inches so I can stick a measuring stick down the plug hole.....I've read in one of the old Sunbeam manuals it gives it as 9/16" BTDC does that sound right?