lamptramp Posted January 2, 2015 Report Share Posted January 2, 2015 My trusty 2002 315R has started to develop a new (and sporadic) issue. When it has been running for a while, it sometimes starts to rev up and down on its own in a rhythmical fashion. Any ideas on where I should start looking for the cause of this? I intend to get the carb off and give it a thorough clean but any other thoughts would be welcome. Quote Link to comment Share on other sites More sharing options...
lineaway Posted January 2, 2015 Report Share Posted January 2, 2015 If you are lucky it could be a dirty carb. At the worst the main bearings and seals are going bad. You could pop the flywheel cover off, grab the flywheel and check for play. You could also have an air leak at the intake boot, that can be checked while running. Use contact cleaner or some other spray while idling and spray around the intake. Quote Link to comment Share on other sites More sharing options...
twinshocked Posted January 2, 2015 Report Share Posted January 2, 2015 Check your spark plug for an "R". The 315 wants a resistor type plug. Quote Link to comment Share on other sites More sharing options...
tail Posted January 2, 2015 Report Share Posted January 2, 2015 Sounds like a blocked pilot jet or maybe your float isnt set right Quote Link to comment Share on other sites More sharing options...
lamptramp Posted January 7, 2015 Author Report Share Posted January 7, 2015 Chaps, thanks for your comments. I stripped and cleaned the carb at the weekend and the problem wasn't there. I checked the flywheel for play and it was solid as a rock. The local bike shop suspects it might be the crank seals (as lineaway suggested), if so it's gonna be expensive to have them do the work. So, if the seals do need replacing I may have to consider having a crack at it myself. I haven't worked on an engine since rebuilding a Ford Escort about 30 years ago, so could someone who has worked on this Honda engine please let me know how straightforward they are to work on? I have certain tools (ie. decent socket sets, torque wrench, etc.) but I guess there will be others that I need to get. Or is it really best to save up and leave this to someone who's properly tooled up? Quote Link to comment Share on other sites More sharing options...
twinshocked Posted January 7, 2015 Report Share Posted January 7, 2015 (edited) Chaps, thanks for your comments. I stripped and cleaned the carb at the weekend and the problem wasn't there. I checked the flywheel for play and it was solid as a rock. The local bike shop suspects it might be the crank seals (as lineaway suggested), if so it's gonna be expensive to have them do the work. So, if the seals do need replacing I may have to consider having a crack at it myself. I haven't worked on an engine since rebuilding a Ford Escort about 30 years ago, so could someone who has worked on this Honda engine please let me know how straightforward they are to work on? I have certain tools (ie. decent socket sets, torque wrench, etc.) but I guess there will be others that I need to get. Or is it really best to save up and leave this to someone who's properly tooled up? PLEASE before you rebuild the motor check the SPARK PLUG for an "R" Edited January 7, 2015 by twinshocked Quote Link to comment Share on other sites More sharing options...
lamptramp Posted January 7, 2015 Author Report Share Posted January 7, 2015 PLEASE before you rebuild the motor check the SPARK PLUG for an "R" Thanks for your concern twinshocked, it is an 'R' plug, I solved that problem a while ago. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.