1st Gear Problems....

[72tiger]

Slowly sorting out my 72 Triumph. When I start it cold and go to kick it into 1st gear it grinds and stalls out the bike. This happens with every start for at least 5 or 6 times until it finally goes into gear and then it shifts smoothly the rest of the time I'm riding it. Even after turning it of and starting again. But if I don't start it for a day or so it fights going into first on startup again. It shift fine into 1st gear when the bike is off. Any ideas whats causing this and how to resolve it?

 

[Rocky]

This seems to be the age-old problem of sticking clutch plates - a well known and common problem.
Before you start the bike pull in the clutch and kick it through a few times. You may feel some resistance at first which is your problem. Keep kicking and the plates will break free and then kick through smoothly.
Start the engine and engage first. I think it will now pop into gear with barely a hint of grinding. A minor "clunk" is common and nothing to be concerned about as it engages.

 

[BAinLA]

Slowly sorting out my 72 Triumph. When I start it cold and go to kick it into 1st gear it grinds and stalls out the bike. This happens with every start for at least 5 or 6 times until it finally goes into gear and then it shifts smoothly the rest of the time I'm riding it. Even after turning it of and starting again. But if I don't start it for a day or so it fights going into first on startup again. It shift fine into 1st gear when the bike is off. Any ideas whats causing this and how to resolve it?

Also check the clutch adjustment before you attempt to ride it again. The instructions are contained on page 20 of your owner's manual. If you don't have one and can't find directions with a search, let us know. -BA

 

[Twin Pots]

It would be fairer to say something is wrong if an old Triumph doesn't do this. My 67 Bonnie crunches into first gear when cold even after unsticking the clutch which absolutely must be done before starting. Even the Triumph manual says this. What makes it better? I tighten up the clutch cable at the handlebar lever before starting. Trial and error will find the point at which the engine will still kick over without slipping too much. I find this allows less crunchy morning starts. I also sometimes while sitting on the bike, if I'm feeling energetic, give the bike a good push forward before engaging first. Once the bike warms up I slack off the cable a little to avoid excessive wear on the clutch mechanism. I would like to hear from owners that have swapped to modern clutch plates to hear if this helps with not sticking. I suspect when we unstick the clutch we are only unsticking possibly one plate due to the small movement on a Triumph clutch. Shame Triumph never addressed the problem. If anyone has a cure do please share. It may not do much harm but it sure always sounds expensive.

 

[Lowboyjim]

It would be fairer to say something is wrong if an old Triumph doesn't do this. My 67 Bonnie crunches into first gear when cold even after unsticking the clutch which absolutely must be done before starting. Even the Triumph manual says this. What makes it better? I tighten up the clutch cable at the handlebar lever before starting. Trial and error will find the point at which the engine will still kick over without slipping too much. I find this allows less crunchy morning starts. I also sometimes while sitting on the bike, if I'm feeling energetic, give the bike a good push forward before engaging first. Once the bike warms up I slack off the cable a little to avoid excessive wear on the clutch mechanism. I would like to hear from owners that have swapped to modern clutch plates to hear if this helps with not sticking. I suspect when we unstick the clutch we are only unsticking possibly one plate due to the small movement on a Triumph clutch. Shame Triumph never addressed the problem. If anyone has a cure do please share. It may not do much harm but it sure always sounds expensive.

 

[Lowboyjim]

ive had less problems since i started using transmisin fluid . and i allways know if the primary is leaking with its red color

 

[Rudie]

72 Triumph.

ive had less problems since i started using transmisin fluid

You have made a fundamental mistake. The engine oil is now likely contaminated with ATF.

You see the large diameter tube from the back of the primary case? That is the crankcase vent; i.e. the crankcase vents through the primary. That is why any Triumph manual for your bike tells you to put engine oil in the primary.

Drain the engine oil and whatever is in the primary and replace it all with fresh correct engine oil.

All '70-on Triumph twin engines vent the crankcase through the primary so, if you have also put ATF in your '71 T100C's primary, you should also replace all its engine and primary oil with fresh correct engine oil.

 

[Lowboyjim]

You have made a fundamental mistake. The engine oil is now likely contaminated with ATF.

You see the large diameter tube from the back of the primary case? That is the crankcase vent; i.e. the crankcase vents through the primary. That is why any Triumph manual for your bike tells you to put engine oil in the primary.

Drain the engine oil and whatever is in the primary and replace it all with fresh correct engine oil.

All '70-on Triumph twin engines vent the crankcase through the primary so, if you have also put ATF in your '71 T100C's primary, you should also replace all its engine and primary oil with fresh correct engine oil.

thanks rudie but i dont own any1970 and newer triumphs so i didnt think about that possiblity , your right and thats good advice but with my bikes i will continue to use atf-- jim

 

[Rudie]

i dont own any1970 and newer triumphs

I have a 56 6t,57tr6,59 bonni,65 t120,66t120c,66t120r and a 71t100c on the road.

https://www.triumphtalk.com/threads/lowboy-jims-t100-thread.52126/
Also, as the o.p. posted:-

72 Triumph.

 

[Twin Pots]

Very good point from Rudie. Those Triumph owners who throw themselves into studying these bikes to handle their own maintenance should already know the later 70's bikes shared engine oil with the Primary case.
Warning here, many owners of older bikes were able to modify earlier bikes by drilling three small holes in the left side crank case below the bearing. This then allowed the engine oil at the correct level to feed the Primary. Draining a little oil out of the Primary case should tell you. The smell of used engine oil is quite distinctive. I suppose one could also reverse engineer (fancy way of saying block up the holes) a later bike so as to allow the use of different Primary oil. It does raise one question. Bikes never run modern oil with friction enhancers due to the clutch being contaminated. With separate clutch oil where is the harm in using modern engine oil with all the new additives?
I always use expensive Penrite Ye Oldie Bike special oil but any thoughts on the subject would be interesting.
I will probably get in trouble for starting a dreaded "oil" thread. So many oils, so many views.

 

[Lowboyjim]

well ya caught me lying. the 71 500cc doesn't have atf in its primary , I havent't rode that bike in over a year its in storage i havent seen it in months thats probably why i said it . ive never been fond of that araingement of the oil system primary sharing oil with the motor, ive seen too much metal in primary cases , ive had a few motors with holes drilled in the case below the crank and have sealed them back up for that reason , i am fusy about the oil that goes to the crank and connecting rods. Well im gona let you guys investagate each other and mind ,my own business!

Also, as the o.p. posted:-