YZ400f - Page 6

JThompson · 05-11-2007, 04:43 AM

Tig saves the day again

thanks for the help buddy

Wopstar · 05-11-2007, 10:10 AM

OK while we are on the subject of rebuilds and problems. What is up with this stupid "Road Draft" tube that Yamaha put on these 400's? All it is good for is putting oil stains wherever I park my bike (mine probably leaks more than normal due to it needing a rebuild right now). Is there any reason that this can't be vented back to the case or even a crankcase filter. I really want to put a K&N breather on this to clean it up a little bit.

tigmaster · 05-11-2007, 10:41 AM

are u talking about the crankcase breather tube? if u are then your bike is overfilled with oil. if it is not please explain the location of the tube.

Wopstar · 05-11-2007, 10:52 AM

I am not overfilling it. I check it every ride because I use so much oil. About 1qt every ride (like I said it is time for a refresh). I am referring to the tube that comes from the top of the rocker cover and then hangs down the front of the engine to the bottom of the frame. I think that mine leaks so much because it needs to be ringed. But I hate the idea of that tube. I really wnt to put a breather filter on it to make it look better and not leave drips in my garage.

tigmaster · 05-11-2007, 11:31 AM

u should be able to put a filter on the tube, it is the exact same concept as on cars. my car has a filter on that tube. and as far as determining if your rings are shot, does your bike blow blue smoke anytime besides startup? oil comming out of that tube would not be an indicator of ring wear. oil is pumped up into your rocker cover area, so oil is always there no matter the condition of your rings. one of the indicators is just blue smoke in the exhaust.

Wopstar · 05-11-2007, 11:46 AM

I don't have any noticable smoke from exhaust even at at start up but like I said I do use approx 1 - 2 quarts of oil per ride. I believe if the rings are gone it will pressurize the crankcase more causing the oil to blow from that vent a lot more.

tigmaster · 05-11-2007, 12:36 PM

i see what youre saying. you usually see blue smoke with worn rings, but not always. have you done a leakdown test? you can do a compression test, but they are not as truthful as a leakdown.

Wopstar · 05-11-2007, 02:22 PM

I have not really worried too much about digging into it right now because I plan on rebuilding it anyway this summer. I did run tests on it at the beginning of the season and the numbers were on the high side but still good. I just hate that breather vent. It seems kind of barbaric technology compared to just running a breather.

Thanks for the help. I am sure that I will be on here a lot when it comes to rebuilding it this summer.

DirtriDER · 05-11-2007, 05:24 PM

im scared the piston is 170 and a set of staniles steel valves are around 80-90

DirtriDER · 05-17-2007, 07:02 PM

got some new parts fork seals, no-toil air filter, and oil and filter change

05-11-2007, 04:43 AM	#51 (permalink)
JThompson Administrator Join Date: Aug 2006 Location: Bellingham WA Posts: 5,163 iTrader: (6)	Tig saves the day again thanks for the help buddy __________________ Tired of ads? Become a member for an almost ad free site! Also we give away monthly prizes just for posting! Register today! Looking for places to ride! Want to review a riding area? Check them out! PRE-ORDER MOTOTIPS Stickers now. Help keep mototips running! Get your order in today! Buy NOW! Special Discounts for members only! Check out our new discount forum for retailers offering to help you save money! Mototips Discounts

05-11-2007, 10:41 AM	#53 (permalink)
tigmaster Administrator Join Date: Aug 2006 Location: Missouri, United States Posts: 7,659 iTrader: (1)	are u talking about the crankcase breather tube? if u are then your bike is overfilled with oil. if it is not please explain the location of the tube. __________________ --'03 CRF450r-- --FMF Pipe, Pro-Tech Revavle-- --Vortex Basket With Tusk Disks And HP Springs-- --Pro Taper Triple Clamps And Bars-- --Devol Full SP With Moose HGs-- --Renthal 13/50 With R1 Chain-- --Now It Is The End, Probably...-- --'06 CBR F4I-- --Bone Stock-- Check Our Latest How-To Here

05-11-2007, 11:31 AM	#55 (permalink)
tigmaster Administrator Join Date: Aug 2006 Location: Missouri, United States Posts: 7,659 iTrader: (1)	u should be able to put a filter on the tube, it is the exact same concept as on cars. my car has a filter on that tube. and as far as determining if your rings are shot, does your bike blow blue smoke anytime besides startup? oil comming out of that tube would not be an indicator of ring wear. oil is pumped up into your rocker cover area, so oil is always there no matter the condition of your rings. one of the indicators is just blue smoke in the exhaust. __________________ --'03 CRF450r-- --FMF Pipe, Pro-Tech Revavle-- --Vortex Basket With Tusk Disks And HP Springs-- --Pro Taper Triple Clamps And Bars-- --Devol Full SP With Moose HGs-- --Renthal 13/50 With R1 Chain-- --Now It Is The End, Probably...-- --'06 CBR F4I-- --Bone Stock-- Check Our Latest How-To Here

05-11-2007, 12:36 PM	#57 (permalink)
tigmaster Administrator Join Date: Aug 2006 Location: Missouri, United States Posts: 7,659 iTrader: (1)	i see what youre saying. you usually see blue smoke with worn rings, but not always. have you done a leakdown test? you can do a compression test, but they are not as truthful as a leakdown. __________________ --'03 CRF450r-- --FMF Pipe, Pro-Tech Revavle-- --Vortex Basket With Tusk Disks And HP Springs-- --Pro Taper Triple Clamps And Bars-- --Devol Full SP With Moose HGs-- --Renthal 13/50 With R1 Chain-- --Now It Is The End, Probably...-- --'06 CBR F4I-- --Bone Stock-- Check Our Latest How-To Here

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05-11-2007, 10:10 AM	#52 (permalink)
Wopstar A Rider Join Date: Sep 2006 Location: Lake Havasu Arizona Posts: 966 iTrader: (0)	OK while we are on the subject of rebuilds and problems. What is up with this stupid "Road Draft" tube that Yamaha put on these 400's? All it is good for is putting oil stains wherever I park my bike (mine probably leaks more than normal due to it needing a rebuild right now). Is there any reason that this can't be vented back to the case or even a crankcase filter. I really want to put a K&N breather on this to clean it up a little bit.

05-11-2007, 10:52 AM	#54 (permalink)
Wopstar A Rider Join Date: Sep 2006 Location: Lake Havasu Arizona Posts: 966 iTrader: (0)	I am not overfilling it. I check it every ride because I use so much oil. About 1qt every ride (like I said it is time for a refresh). I am referring to the tube that comes from the top of the rocker cover and then hangs down the front of the engine to the bottom of the frame. I think that mine leaks so much because it needs to be ringed. But I hate the idea of that tube. I really wnt to put a breather filter on it to make it look better and not leave drips in my garage.

05-11-2007, 11:46 AM	#56 (permalink)
Wopstar A Rider Join Date: Sep 2006 Location: Lake Havasu Arizona Posts: 966 iTrader: (0)	I don't have any noticable smoke from exhaust even at at start up but like I said I do use approx 1 - 2 quarts of oil per ride. I believe if the rings are gone it will pressurize the crankcase more causing the oil to blow from that vent a lot more.

05-11-2007, 02:22 PM	#58 (permalink)
Wopstar A Rider Join Date: Sep 2006 Location: Lake Havasu Arizona Posts: 966 iTrader: (0)	I have not really worried too much about digging into it right now because I plan on rebuilding it anyway this summer. I did run tests on it at the beginning of the season and the numbers were on the high side but still good. I just hate that breather vent. It seems kind of barbaric technology compared to just running a breather. Thanks for the help. I am sure that I will be on here a lot when it comes to rebuilding it this summer.

05-11-2007, 05:24 PM	#59 (permalink)
DirtriDER C Rider Join Date: Apr 2007 Location: Crab Orchard, KY Posts: 136 iTrader: (0)	im scared the piston is 170 and a set of staniles steel valves are around 80-90

05-17-2007, 07:02 PM	#60 (permalink)
DirtriDER C Rider Join Date: Apr 2007 Location: Crab Orchard, KY Posts: 136 iTrader: (0)	got some new parts fork seals, no-toil air filter, and oil and filter change

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