Valve Lapping or Grinding - Page 3 - Triumph Forum: Triumph Rat Motorcycle Forums
Air Cooled Twins Technical Talk Technical Talk for Hinckley Triumph Twins: Bonneville, Bobber, T100, Speedmaster, America, Thruxton, and Scrambler.

Sponsored by: Triumph Twin Power Ltd

LinkBack Thread Tools Display Modes
post #21 of 25 (permalink) Old 12-15-2012, 04:02 PM Thread Starter
Main Motorcycle: Standard 2007 Bonneville
Senior Member
conchscooter's Avatar
Join Date: Aug 2007
Location: Florida Keys
Posts: 397
The original thought was that the mechanic had screwed up and he was devastated but upon removing the head there was no evidence of damage. Lots of carbon and loose valves in their seats.

The argument about replacing the rings is interesting becaus eyes, on the one hand doing the valve job changes the relationship between the valves and the rings, but on the other hand replacing the rings...changes the relationship between the piston and the cylinder. Hmm....
There a 2007 Black with 143 miles on the clock for $5400 just waiting to get an owner that will ride the snot out of it! Hmm...luckily I just got a new car so a new bike at least is out of the running.
conchscooter is offline  
Sponsored Links
post #22 of 25 (permalink) Old 12-15-2012, 07:12 PM
Main Motorcycle: 03 T100
Senior Member
mikeinva's Avatar
Join Date: Mar 2007
Location: richmond va
Posts: 8,841
Send a message via AIM to mikeinva
If your bike is paid for you can do the head up right and a 904 and have a much better running bike for less money that you can ride for years

Why do I feel young on my bike
mikeinva is offline  
post #23 of 25 (permalink) Old 12-17-2012, 04:51 AM Thread Starter
Main Motorcycle: Standard 2007 Bonneville
Senior Member
conchscooter's Avatar
Join Date: Aug 2007
Location: Florida Keys
Posts: 397
Long since paid for. Where I live I am 12 hours riding time from the nearest mountain, 100 miles from the nearest freeway and in all respects happy with the performance of the original bike, which is where I wish to return after the interruption of these irritating holidays shuts everything down.
conchscooter is offline  
post #24 of 25 (permalink) Old 12-30-2012, 04:17 AM
Grand Prix 250
Main Motorcycle: 2001 Bonneville
Join Date: Jun 2006
Location: Cairns, Queensland, Australia
Posts: 69
Other Motorcycle: 2003 Bonneville
Combustion residue build up on top of the piston is burnt oil. Just check that the bore is OK then measure your ring gap, it has probably opened up allowing oil to be carried up past the rings. Take out all of your valves and get a shop to re-face them all, light lap with fine paste and blue the face back in to ensure that there is a seal all of the way around, only light amount of blue and slight turn to ensure that you are not wiping the blue all around the seat. Check the ring gap in the liner, if it is less than minimum you will have to see a mechanic and get him to gap them for you.
Now the tricky bit when you put the old girl back together, you have to run it in and if it is not done properly you will start burning oil again. I used a 30w Mineral Oil and when I started the bike, checked for leaks quickly, took it out on the road and ran it out to around 7,000rpm in second (depends how game you are with the police) held it there for a few seconds and then slowed down. Did this a couple of more times for the first 20-30Klm to bed in the new rings. Changed the oil back at around 200klm to the recommended product and mine has not used oil since the second rebuild, first one i @#$%^d it up and did not run it in properly. But like Mikeinva said a 904 kit is heaps of fun! and for the cost of doing a rebuild like above, if you cant do it yourself, then it may be cheaper to go the BBK.
Grinder is offline  
post #25 of 25 (permalink) Old 01-03-2013, 05:21 PM
Main Motorcycle: 2006 T100
Senior Member
Join Date: Aug 2009
Location: Florida
Posts: 1,295
Other Motorcycle: 1968 Triumph T120
Would you PM with the name of the shop you use. I need the valve adjustment done -- the guy I had been using moved out of the Keys. Many thanks.

2006 T-100, 57k and oil tight; BC Sleepers, no snorkel,Hyde steering damper, Parabellum Scout, Western Bars, Progressive 412s, Michelins, AirHawk, Go Cruise, 19-tooth; Givi bags, K&N, Nology, Kuryakan Iso grips
Oldguy is offline  
Sponsored Links

Quick Reply
All posts must adhere to Forum Rules

Register Now

In order to be able to post messages on the Triumph Forum: Triumph Rat Motorcycle Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter your valid email address, that can receive an automated confirmation message. Otherwise, you won't be able to gain full access.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
Bedding/Lapping Piston Rings. Mr.Pete Vintage Technical Tips & Tricks 19 06-28-2015 07:02 AM
Valve cutting/grinding on T140 Aircool Classic, Vintage & Veteran 4 10-19-2012 08:51 PM
lapping valves. jimmy bush Vintage Technical Tips & Tricks 1 04-27-2009 04:51 PM
breaking(lapping) in a new engine dolson Maintenance Tips and Tricks for your Sprint 71 03-26-2009 04:04 PM
Grinding the pegs yes but grinding the exhaust? tazwolf Hinckley Classic Triples 17 10-01-2005 08:34 AM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are On

For the best viewing experience please update your browser to Google Chrome