Triumph Rat Motorcycle Forums banner

1 - 12 of 12 Posts

·
Registered
Joined
·
36 Posts
Discussion Starter #1
72 daytona
exhaust cam 70-9987, 71-0043
intake cam 70-1064, 71-0043
engine xg-41993
Trying to figure out what i have.
 

·
Registered
Joined
·
36 Posts
Discussion Starter #4
Family day is good grandpaulz. I found out that the 71-0043 is just the blank cam number. The intake cam number 71-1064 is for a 70
t100c which might be the same for a 72 t100r? Any ideals on this? The exhaust cam number 70-9987 i can't find but i found a 70-9986 number which says it is for a 70 t100c. So i am looking for this 70-9987 exhaust cam number to see what it is for and if the intake cam is generic from the c to r models then i will know if i should line up the dots or lines on my cam gears.
 

·
Registered
Joined
·
36 Posts
Discussion Starter #5
One last bump to try and find this 70-9887 exhaust cam number. Like to know what model/year of bike this is for.
 

·
Registered
Joined
·
625 Posts
Found This Page which states it's a unit 500 exhaust cam for up to '68. I don't know if the earlier exhaust cams will work in the later cases ... I know that they did a lot of changing for camshafts in the T100's.

I also found This Page which lists that cam in the 'High Performance 3134' section, which leads me to believe that it's the Daytona grind.

As of (I think) '70, C and R models used the same intake, but a different exhaust. My '70 T100C (bitsa) is running a set of '69 cases with '70+ Daytona profile cams and R radius tappets on both sides. It seems pretty happy.

I don't remember what the number was on my exhaust cam, but I do remember that it was weird and we had a very hard time tracking it down ... we may have the same exhaust cam. It's probably one of those Triumph part number supercede situations.
 

·
Registered
Joined
·
36 Posts
Discussion Starter #7
Thanks t100RC for the info. It still leaves me guessing what model it is for but closer than what i could find for info.
 

·
Registered
Joined
·
625 Posts
I wouldn't be so concerned about knowing exactly what it came from. Be satisfied knowing that its the '3134' profile. That makes it the performance version.
 

·
Registered
Joined
·
36 Posts
Discussion Starter #9
Thanks again T100rc with your info and back to my parts book tells me i have the right cams. The numbers match up. Now the r radius tappets, is there any way to tell what tappets i have without tearing the bottom end apart? I heard the t100r's are 1 1/8 and the c's are 3/4. Is this the length of the tappet or did these numbers change on the newer models. My parts book list's part numbers but no measurements. Looking into the cam hole with the cam removed looks like the tappet is only 3/4 inch long. Sorry for all the questions but i am new to these old brit bikes.
 

·
Registered
Joined
·
1,458 Posts
1 1/8" and 3/4" refer to the radius of the foot on the follower (tappit). What this means is, the 3/4" radius allows the valve to open and close quickly where as the 1 1/8" being longer (circumference of a circle) opens the valve earlier and closes it later for the same lobe centre.
Roy.
 

·
Registered
Joined
·
625 Posts
R tappets will be stamped 'R' on one side of the base. If you can see the numbers on your cams, you should be able to see the tappets ... dunno how you see those numbers with the cylinder still installed ... unless you extracted the cams leaving the jugs on the bike. The tappets are in the top end ... they're right at the base of the cylinder.
 

·
Registered
Joined
·
36 Posts
Discussion Starter #12
laid the bike on it's side to pull the cams out of it. Shined a light in there to see the tappits. I don't see any markings on them. This bike has never been fired in over 20 years. Someone else has rebuilt the bottom end and then the bike sat for 20 years. I did the top end then started second guessing the bottom end when i seen the timing marks were on the dots and not the lines. Amazingly the bottom end still has alot of assembily lube in it.
 
1 - 12 of 12 Posts
Top