Triumph Rat Motorcycle Forums banner
  • Hey everyone! Enter your ride HERE to be a part of this month's Bike of the Month Challenge!

1 - 7 of 7 Posts

·
Super Moderator
Joined
·
13,270 Posts
The tolerance is given in the technical spec section of the shop manual, which I don't have at hand this very moment.

If you can perceive a bit of slop, it's probably too much.

Was your bike smoking?
 

·
Registered
Joined
·
372 Posts
Discussion Starter · #3 ·
Thanks GrandPaulZ,

To answer your question, yes, the bike was smoking and yes, I do need four new valve guides. They definitely are worn. The manual states that the exhaust valve stems call for .3090 to .3095 inches whereas I am reading .3085 on the main stem.
I guess I was wondering if 5 thou was significant enough on valve stems? This stem wear is the only defect
 

·
Registered
Joined
·
372 Posts
Discussion Starter · #5 ·
I think that I will definitely change the exhaust valves. The inlet valves look like new. Where does it end? Ideally the con rod shims should be changed out as well. new wrist pins etc.I am at the limit of having to oversize.
 

·
Registered
Joined
·
1,034 Posts
the wrist pins are free . they come with your new oversize pistons ;)

i'm assuming you're not going to do the guide replacement or valve grinding yourself , so i'd recommend having your machinist check out your components .

some things slightly out of tolerance can mean maybe a little loss of performance while others can mean catastrophic failure .

check out http://www.mapcycle.com/index.asp they carry the black diamond valves if you find you need new ones .

cheers , Woody
 

·
Registered
Joined
·
810 Posts
Thanks GrandPaulZ,

To answer your question, yes, the bike was smoking and yes, I do need four new valve guides. They definitely are worn. The manual states that the exhaust valve stems call for .3090 to .3095 inches whereas I am reading .3085 on the main stem.
I guess I was wondering if 5 thou was significant enough on valve stems? This stem wear is the only defect
Your only 1/2 thou .ooo5 underspecs not 5 ;not to say if you need replacement or not
 
1 - 7 of 7 Posts
Top