Tosh1218 592 Posted December 1, 2018 I'm not mechanically minded so hope this isn't a daft question to some of you . On today's modern. GM engines there is a colured tab Black,green ,red etc what does this signify if anything ? Thanks in advance Share this post Link to post Share on other sites
*JJ 512 Posted December 1, 2018 Nothing. It is just a plastic segment which covers the cam sprocket. Share this post Link to post Share on other sites
foamfence 2,917 Posted December 1, 2018 44 minutes ago, *JJ said: Nothing. It is just a plastic segment which covers the cam sprocket. It actually denotes what stage the servicing is at, some engine builders change different parts at different services and that is a way of keeping track. 1 Share this post Link to post Share on other sites
MrMungo 708 Posted December 2, 2018 20 hours ago, Tosh1218 said: I'm not mechanically minded so hope this isn't a daft question to some of you . On today's modern. GM engines there is a colured tab Black,green ,red etc what does this signify if anything ? Thanks in advance Usually just used by the rider to more easily identify between the different engines he owns. 1 Share this post Link to post Share on other sites
Oafski 174 Posted December 2, 2018 On 12/1/2018 at 10:14 AM, foamfence said: It actually denotes what stage the servicing is at, some engine builders change different parts at different services and that is a way of keeping track. Green- Just been serviced, Black- Needs an Oil Change, Red- About to blow up. 1 3 Share this post Link to post Share on other sites
IronScorpion 1,407 Posted December 2, 2018 I thought it denotes the type of engine tune it has had. Oil is changed every 2-3 heats or should be according to PJR tuning. Share this post Link to post Share on other sites
Bald Bloke 3,287 Posted December 2, 2018 (edited) On 12/2/2018 at 2:01 PM, Oafski said: Green- Just been serviced, Black- Needs an Oil Change, Red- About to blow up. Green = blew to bits I've never noticed mechanics changing the valve cover off and changing the colours every 3 -5 races after a change of oil Edited December 4, 2018 by Bald Bloke Share this post Link to post Share on other sites
*JJ 512 Posted December 3, 2018 19 hours ago, IronScorpion said: I thought it denotes the type of engine tune it has had. Oil is changed every 2-3 heats or should be according to PJR tuning. Ours (now sold) had a proprietary cover with 'Ashtec Eng.' on it. When it got too shabby, I bought a black plastic one to replace it when the engine was rebuilt (black mainly because I thought is looked more flash!). We changed the oil after every meeting, but this was in amateur/MDL level. Share this post Link to post Share on other sites
GWC 495 Posted December 6, 2018 On 12/2/2018 at 3:35 PM, IronScorpion said: I thought it denotes the type of engine tune it has had. Oil is changed every 2-3 heats or should be according to PJR tuning. If that’s the case then no wonder the cost of racing is out of control! Share this post Link to post Share on other sites
martinmauger 584 Posted December 6, 2018 (edited) Continuing with engines, could someone please explain what the term 'off-set engine or crank' means again please. I had a link to a website which listed many such interesting technical details but don't seem to be able to find it. Thanks in advance.... Edited December 7, 2018 by martinmauger spelling (sigh) Share this post Link to post Share on other sites
foamfence 2,917 Posted December 6, 2018 8 minutes ago, martinmauger said: Continuing with engines, could someone please explain what the term 'off-set engine or crank' means again pease. I had a link to a website which listed many such interesting technical details but don't seem to be able to find it. Thanks in advance.... https://www.rideapart.com/articles/256853/free-power-offset-cylinders-explained/ 2 Share this post Link to post Share on other sites
martinmauger 584 Posted December 7, 2018 That's it, thanks.... Share this post Link to post Share on other sites
piston197 196 Posted December 7, 2018 There is not a lot new in the world, this was being done many years ago particularly in scooters, but rather than having offset cranks, they were doing it simpler by having the gugeon pin off centre ( de-saxe) to minimise the side thrust of the piston, just had to be careful that you fitted the piston in the correct way round Share this post Link to post Share on other sites
martinmauger 584 Posted December 7, 2018 (edited) 6 hours ago, piston197 said: There is not a lot new in the world, this was being done many years ago particularly in scooters, but rather than having offset cranks, they were doing it simpler by having the gugeon pin off centre ( de-saxe) to minimise the side thrust of the piston, just had to be careful that you fitted the piston in the correct way round Never down that but managed to fit a throttle slide the wrong way round once, though it wasn't on a speedway bike. One never fogets the terror of a throttle stuck wide open . Then one gives much praise and thanks for the invention and fitting of the kill switch .... Edited December 7, 2018 by martinmauger added horror Share this post Link to post Share on other sites