wonder boy Posted June 1, 2004 Report Share Posted June 1, 2004 Just a quick question? When I ride on the on flat ground I hear a knocking noise in the cylinder, is this normal with all bikes or just some bikes. My bike is a 2001 Montesa. Gavin Quote Link to comment Share on other sites More sharing options...
bigfoot Posted June 1, 2004 Report Share Posted June 1, 2004 Is it just on flat ground? It's probably pinking but without more info we'll struggle to help. It's usually easy to check pinking by giving it some sharp bursts of power. Pinking usually shows up just as you let off as a sharp knock. Quote Link to comment Share on other sites More sharing options...
wonder boy Posted June 1, 2004 Author Report Share Posted June 1, 2004 Yeah its only flat gound. I thought there might be a problem but people it happens to all bikes on thw road (trials). Gavin Quote Link to comment Share on other sites More sharing options...
bigfoot Posted June 1, 2004 Report Share Posted June 1, 2004 I've never heard of a bike that knocks of flat ground and is fine without more investigation. As I said it could just be a little pinking and that would be OK as long as its not to bad. Pinking does create forces on the top end that will eventually damage it if left unchecked. I would suggest you get someone in the know locally to listen to it and advise you. Quote Link to comment Share on other sites More sharing options...
monty-python Posted June 3, 2004 Report Share Posted June 3, 2004 As bigfoot says, if it is pinking (my 99 mont did this too), it will knock just as you shut off from a blast of throttle. I found that using better fuel helped (optimax or good old 4 star, if you can get it.) Quote Link to comment Share on other sites More sharing options...
landrover Posted June 4, 2004 Report Share Posted June 4, 2004 As bigfoot says, if it is pinking (my 99 mont did this too), it will knock just as you shut off from a blast of throttle. I found that using better fuel helped (optimax or good old 4 star, if you can get it.) my montesa does the same (2002) model and i use optimax all the time mixed @80:1 just wondering if anyones tryed any of the octane boosters that are available Quote Link to comment Share on other sites More sharing options...
spencey Posted June 4, 2004 Report Share Posted June 4, 2004 I'm using optimax with STP octane booster in my 300 Fantic(which also knocks when it's hot).This combination definitely reduces the detonation. I got the STP from halfords(it comes in an orange bottle).It also seems to work well enough with Super plus unleaded. Bear in mind my bike would have been designed to run on 98 octane leaded petrol so you modern petrol heads should get equally good results. Cheers, Quote Link to comment Share on other sites More sharing options...
landrover Posted June 5, 2004 Report Share Posted June 5, 2004 I'm using optimax with STP octane booster in my 300 Fantic(which also knocks when it's hot).This combination definitely reduces the detonation.I got the STP from halfords(it comes in an orange bottle).It also seems to work well enough with Super plus unleaded. Bear in mind my bike would have been designed to run on 98 octane leaded petrol so you modern petrol heads should get equally good results. Cheers, what is the ratio that you use ie 1.5%,2% also do i need to add xtra oil to keep the 80:1 mix correct Quote Link to comment Share on other sites More sharing options...
marky g Posted June 5, 2004 Report Share Posted June 5, 2004 I'm using optimax with STP octane booster in my 300 Fantic(which also knocks when it's hot).This combination definitely reduces the detonation.I got the STP from halfords(it comes in an orange bottle).It also seems to work well enough with Super plus unleaded. Bear in mind my bike would have been designed to run on 98 octane leaded petrol so you modern petrol heads should get equally good results. Cheers, Don't listen to Spencey, he knows **** ALL !! Quote Link to comment Share on other sites More sharing options...
subira Posted June 23, 2004 Report Share Posted June 23, 2004 I've always felt that the Monty knocking is definitely octane related, others reckon its jetting - the only cures I have found are either 4 star (99.7 RON) or elf GPM-2T (100 RON). As the elf fuel is very expensive, dig out a localish 4 star pump. You can find your nearest 4-star via: http://www.leadedpetrol.co.uk/list.htm 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.