Author Topic: side valve owners  (Read 1929 times)

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Offline bangers-c10

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side valve owners
« on: March 24, 2018, 01:37:48 am »
ok guys i know the old side valve isnt a power plant, this will all be about top gear /3rd.....  seems to be getting worse. when i first set off it  goes into 3rd and the more i twist throttle faster it goes which is fine.. but after a bit of a ride,and its hot...riding in 3rd is like riding with a head wind, yes it slowly picks up but seems no mateer if i have throttle wide open or on half there is no difference, or if im putting along half throttle and then twist it to full throtte ,there isnt any pick up in revs at all,,,,,,,

could it be that carb/intake is getting to hot and evaporating fuel  --  ---it does have a 1/2 inch bakelite spacer.     maybe make it thicker?

could it be auto advance isnt working right?
has new valves,,maybe i need to go smaller on the tappet gaps?
I think shes just getting to hot

has anyone here had to hold there sidevalve wide open for a period of time/head wind so on.      does it end up getting tight on you?
Also after stopping/turning off bike,, white ish smoke comes out of exhaust for few seconds.. and motor seems real hot.


running 90 main jet, tried  80   has more pick speed but plug looks lean when checked.

Offline Ginge

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Re: side valve owners
« Reply #1 on: March 24, 2018, 04:37:45 am »
I campaigned a Triumph on the Gold Coast for a few years then shipped it to NZ where it needed a complete re-jet.  Aussie is hot.  I ran richer settings there and more retarded timing.

In the cooler NZ climate I  can run leaner with more advance.

Don't go smaller on the tappets.  Go bigger.  In Aussie I ran an extra 2 thou over spec. One for the heat and one for luck.  It clattered a bit when cold but that stopped when it warmed up.

Different bike and OHV but the heat I think is your issue.

White smoke out of the exhaust when you switch off is probably oil burning off in the cylinder or exhaust.  Not a huge issue but indicates the engine is working hard.



Ginge.

Offline bangers-c10

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Re: side valve owners
« Reply #2 on: March 24, 2018, 04:41:27 am »
has anyone with a early c10 here tried a 100 jet instead of 80-90     i been thinking of buying one to try but when i pull plug out to inspect with 90 jet it looks to be on the edge of to rich, ring is black but centre is a good light tinge of red, to me thats pretty good, when i put 80 jet in its mostly all white ish, too lean..   

I know guys,with out looking at the bike its hard to pin point,    but its really annoying me how it bogs down under load after it gets hot. 
I did mention once before it got so hot it started to bind up and nearly stop. was way to hot, i just dont push it as hard anymore,
but  wondering about putting higher jet might sort it out,   I know theres only one way to find out i guess.

Offline bangers-c10

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Re: side valve owners
« Reply #3 on: March 24, 2018, 04:45:06 am »
hi Ginge , sounds about right, its always stinking hot on most rides, And she sure does get hot the old girl,, iwill try bit richer,and play with timing a bit, 

Offline MilitaryRon

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Re: side valve owners
« Reply #4 on: March 24, 2018, 05:27:42 am »
Retarding the timing from standard, will make it run hotter. Ron

Offline Ginge

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Re: side valve owners
« Reply #5 on: March 24, 2018, 06:54:41 am »
I agree Ron.  Advancing or retarding from optimum will make any bike run hot.

It comes down to whatever tuning keeps the bike happy in its environment.

Bangers,  if you take it for a spin in the early morning ( cooler more dense air ) does it still misbehave?  If so then I'd be thinking about oil flow, oil weight and oil cooling.

If it runs better in the cool ( most do ) then it is more likely jetting and air flow.  What filter are you running?  What happens if you run the bike in the heat without the filter?

Ginge.

Offline timsdad

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Re: side valve owners
« Reply #6 on: March 24, 2018, 07:57:53 am »
I'd go up on the main jet, perhaps up to about 120, because too big is ok but too small isn't. It will only affect high throttle openings and rolling the throttle off a bit if it's labouring will show an improvement if it's too rich. I then come down in sizes until it makes no difference and plump for the bigger one.

Also, run it as advanced as possible without pinking because too advanced is better than too retarded.

If it's suffering from fuel vaporising in the carb, and needs a heat-proof spacer, this will usually only occur when the bike is stopped after a run and the heat transfers back from the hot engine to the carb float chamber. I've never had it happen when the bike is being ridden, or even if the engine is still running after a trip.


Ray
Just a motorcyclist.

Online Owen

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Re: side valve owners
« Reply #7 on: March 24, 2018, 08:02:58 am »
My 53 C10 has its own way. Sometimes it will go well and others not so.  It likes running in humid air more than dry (as Ginger said)  I've tried texting but not enough difference to keep it that way.
How many miles have you done since the engine was rebuilt (if you have). Mine took over 1,500 miles till she would allow long periods of high revs.
Do you have an iron or aluminum head.  If iron can you try an aluminum one?
« Last Edit: March 24, 2018, 08:26:48 am by Owen »
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc

Offline ianinglis

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Re: side valve owners
« Reply #8 on: March 24, 2018, 09:24:10 am »
as ray said i would allways run rich rather than weak
i think the issue is the timing advance / retard so check its working ok or something is going to melt or burn out

ian
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BSA C10L 1954 - MVE 107
RM6 RALEIGH RUNABOUT
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Online Owen

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Re: side valve owners
« Reply #9 on: March 24, 2018, 12:30:14 pm »
What is you spark plug like in colour?
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc

Online Cosmikdebriis

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Re: side valve owners
« Reply #10 on: March 24, 2018, 03:07:13 pm »
What is you spark plug like in colour?

Have a look at his first few posts  ;)
A bike on the road... Is worth two in the shed...

Online Owen

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Re: side valve owners
« Reply #11 on: March 24, 2018, 05:02:44 pm »
Doh with the plug colour. 
What is the air temperature when you are riding the bike?
1940 C12 (350cc)
1945 C10 & C11
1953 C10 & C11
Anyone want a B20 in need of a lot of tlc

Offline sidevalve

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Re: side valve owners
« Reply #12 on: March 24, 2018, 09:22:02 pm »
Just a simple point what fuel are you using ? My old M21 was happier on the cheapest lowest octane fuel I could find and I even remember one old guy telling me he used to mix 10% paraffin in with his petrol on his M20

Offline bangers-c10

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Re: side valve owners
« Reply #13 on: March 25, 2018, 02:42:03 am »
I havent got a 100-120 jet as yet as its the week end, i will asap.
It does run better in the cool yes ,but soon as she gets hot its like hitting head wind, an have to back right off throttle to let her cool down or it just gets slower and slower.
Dont run a air filter never have.
def havent done 1500 miles since rebuild ,prob about  200 miles max maybe 300.
i always try to put 98 octane in it,      lately a drop or two of T2 in it,  to keep rings from burning out,
it has a Iron head. ive tried to find a alloy one with no luck.
air temp on most days are around 25-35 degrees .
paraffin  thats just kero isnt it?

I will try bigger jets, then if no changes i will check ad/retard  springs ..



its ok putting around, but yeah if theres a head wind or traffic, and need to open her up, it just gets slower and slower to point of no power at all... it has stock piston with new rings new valves,new needle bearings in big end.
I will report back once ive tried bigger jet..

Online Cosmikdebriis

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Re: side valve owners
« Reply #14 on: March 25, 2018, 09:48:28 am »
Assuming piston to bore clearances are correct. I think things may improve after a bit more running in.

I would be inclined to remove the barrel though and have a look for score marks on the piston that would only exacerbate the situation.
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