scdirtdobber
06-04-2009, 02:05 PM
Hi,I'm glad to have found this site!! I guess for starters I have been riding atv's for about 14 years and work on most of the locals when they tear up all which are utility models.I purchaced a new 07 400ex from a local dealer 3 weeks ago.I rode it about 30 minutes the first day and noticed some light puffs of smoke when it got up to temp,I figured it was exhaust packing if they have any,the second day I rode it for about 2 hours and same deal when it gets hot I get light puffs of smoke.I called the dealer and he said it was possibly the new burning out the pipe or it is jetted rich which I doubt.Well here it is over 2 weeks later and 12 hours on the bike and it still puffs,more so if it's in neutral and when it's revved it a bit,I cannot tell the color or tell if it's fuel or oil nor distinguish the smell,the tip of the pipe is super clean so it's not rich.I changed the oil early at 10hrs with GN4 hoping it was the factory oil breaking dow but it's not.After about the 6th hour I noticed alot more engine noise when it's hot but not the valves,is the 400 engines generally noisy compared to Honda's utility atv's.I plan on checking the valves next week,is there anything special on one of the valves that has to be done different seeing it has a internal decompression lever,I'm thiking on the right exhaust valve,I've adjusted alot of Honda valves but not on this model,usually Foremans,rincons ect.