engine

Hi guys, I'm picking back up on this project as I've been busy the last 9 months or so with a new business. I received a bike mostly in boxes but with a title from a friend for free. I'm at the point now where I have a few issues I'm having a hard time thinking through. I can get the...

Story so far. Bought an 83 XS400 with a well worn 6 speed DOHC motor. So bought another motor, 5 speed and put it in. Installed new front and rear wheel bearings, Installed new swing arm bearings and shaft. Removed the forward third of the air box. And painted the main parts an ugly purple, that...

Hi, hope somebody can help. I was out today on the XS400 and as I slowed at traffic lights the bike cut out. I managed to get it going but a mile or so down the road it did it again. When I got home and removed the plugs they were really sooty and black, the left one slightly more than the...

I took apart my head today and noticed that my left intake valve stem is slightly bent towards the top middle. The valve guide didn't seem to have any weird scarring on the inside neither did the the actual valve stem. So am wondering if it got bent when the bike was put to pasture or worse...

Hopefully someone can help me out last week I was riding home when outta of no where the right cylinder stopped firing I pulled over had a drink and after about 10 minutes I started it up and it was running on both again I almost made it home and it started missing again I figured it was a bad...

Hey all just wanted to share, not sure how many sets they have but this is where I got the replacement rings for my 81 400. Pretty cheap compared to a few other vendors and their shipping was very good as well. They are actual Yamaha Rings too...

So I recently adjusted my idling screw slightly because my bike was idling very low, (around 800 RPMs) and was sometimes dying as a result. I barely touched it, just enough to get the idling RPMs around 1200. That was last week and it's been riding fine. But today I get on it, give it some...

Anyone know if an XS650 gear train cover gasket for 1972-84 fit my 81 XS400? Really don't want to buy a $50 gasket set and the gasket is half stuck on the block and half on the cover when I try to take it out. :doh: This is the part I'm thinking of: http://www.mikesxs.net/product/18-0859.html

I purchased a 1980 xs400g a few weeks back and I just can't get it up and running for more than a day at a time with no problems. I'm about to call it quits and sell it if I can't get it running soon because it's becoming a bit too pricey and time consuming trying to just get her out the...

hey guys, another question, 1980 xs400. im making it a kick only.. do i still need the solenoid??? cant i just run the starter motor wire off the positive, and then another wire off the positive to a switch then to the main fuse going to the coils and ignition unit? keep in mind, i really am not...

Hey all just wondering if someone can tell me about buying a new cam chain. My question is, if you buy a cam chain advertised as specific for your model does it come the correct length and ready to fit out of the box or do you need to measure it up and take links out if necessary? I guess the...

Seems like replacement is a no-brainer but the PO must have been running the bike for some time with it in this condition: Discovered it while cleaning the engine in preparation for a full rebuild. Decent replacements on Ebay aren't too cheap. Would I be asking for trouble putting it back on...

I'm in the process of resurrecting a SOHC XS400 and was wondering if anyone knew of any sources of stiffer valve springs, be they new or re-purposed from another bike... As of now, the plan is a Megacycle cam, stock rockers hardfaced by Delta, gentle porting/polishing to remove...

Probably opening a can of nasty worms here. But, whats everyone like for plugs? THis would be for my 81 xs400. Typically I have always stayed with the type of plug the manufacturer recommended or style of plug from around that year(s) of engine. But this was with cars and trucks. I know...

I rode my Dad's '81 for a few years with no problems at all.:bike: It ran amazing and has clean carbs. Last year I didn't ride it at all, but the second time I started it I got 300 yards down the road and it killed. Spewed oil all over the road out of the right exhaust. Last night I started...

I have been searching for different pistons to replace the almost obsolete xs400 pistons. After looking through a lot of part diagrams I stumbled on these guys. KAWASAKI KLF250 Bayou 03-11 Piston They look very similar to the xs400 OE pistons, but run a slightly lower compression height...

Hi chaps! I just tore down a xs360 motor and was comparing the differences between it and the 250 motor. I have a 250 head and rocker cover here and a 250 gearbox. And was comparing the differences between them and the 360 motor. After a quick eyeballing, apart from the barrels I saw very...

Hey everyone, same thing as last time, I ordered another new gasket and it wasn't exactly hard to find, but it wasn't super easy so I thought I would scan for my own use and thought since you guys may eventually need one and like making your own gaskets here i would post up the scanned image...

Hi! I have some major problem during my engine reassembly. I've done everything with manual and yet i can't get my gear drum working properly. I didn't dismantle gear shafts and gear drum. I just pull it out from crank case. After refitting drum change i had problems with finding...

I have cleaned and rebuilt the carbs, which have all the original stock jets. And yes, they are very clean! When I fire up the engine, it seems like only the right side is working. If I pull the right plug wire off, the engine dies. Pulling the left wire does nothing. If I have full enricher...