french xs400

[niko]

hello,
i've bougth a 400xs se 4g5 motorcycle 2 month ago.
I'm very happy and i want to do a dirt track.

the motorcycle didn't start since 5 year i think. the history of this motorcycle is very fuzzy...
i've cleaned carrb, changed diaphragm and I managed to restart the last week!

the right cylinder seems smoke more than the left and the exhaust seems more hot.

i want control the engine but it's not my job and i'm not an expert! i've.

I pulled off the engine but before opened and control i'm looking for the service manual.


I've bought the haynes manual but only in eglish, i've downloaded the service manual for the 400seca (in english, french, german). This manual is perfect but it isnt the sme engine!

can you help me to find the same service manual (in three language) but for 400xs se?

Tks and sorry about my english...

If you want, with friends we have a blog where you can find the progress on my xs and more
http://weepateam.blogspot.com/

 

[gentlemanjim]

Bonjour Niko, I know there is a multi lingual version posted here of the service manual. Is your SE a SOHC or DOHC? And it sounds like you are only running on one cylinder.

aurevoir

 

[drewpy]

Bonjpur mon ami!
que est qe se? (that's it for my french, pardon!)

its a single cylinder xs twin :lol:

the carbs are still not cleaned properly, you need to REALLY strip them down, ultrasonic cleaning is the way to go.

 

[niko]

i don't think the bike turn only on one cylinder.

the first time i started the bike, it turned only on right cylinder. The left exhaust was cold and this confirmed what i thougut about this bike because when i bought the motorcycle the right exhaust (collecteur) was blue but not the left!

It ws the reason i've cleaned the carb (changing all the pieces with the motorbay kit).

Now when i start twice are hot but perhaps the right was more! and the right smoked "black" more!
Perhaps because the bike turned a lot on signle cylinder and the right cylinder is more dirty?

on those pictures you can see one side is more black!
the "segment" seems ok but it's very black for me! because??

This afternoon i opened the engine, i 've a problème with a dowel pin!!

(sorry, sorry, and sorry about my english...)

 

[gentlemanjim]

Black sooty combustion chamaber means rich fuel mixture. As Drewpy says clean them thoroughly. Also they may be jetted incorectly by a preious owner. Check the number on the pilot and main jet and copare with the manual. IF the slide needle has multiple positons agin put it back to the palce as specified in the manual. I've played plently with changing jets and stock usually works out best.

Go here: http://www.xs400.com/forum/showthread.php?t=4503&highlight=manuals
Post 2 Part 2

 

[niko]

i ve cleaned carb yet and i think the problèm is solve:

dismantled carb and changed diaphragm. you can see on picture one of needle was dirty
here

cleaned carb
here

reassembled carb
here

 

[gentlemanjim]

tres bien

 

[niko]

about the piston ring set and the clearance betwenn piston and culasse:

how measured the clearance, it seems very precise

for the piston ring: i mesured 0.6 for the highest (0.15-0.35 technical review)
0.4 for the middle (0.2-0.4mm technical review) and 0.7 for the lower (oil) (0.2-0.9 technical review)
should I change?? i think it ll be good but i don't find piston ring saler. can you help me?

 

[niko]

i don't find piston ring in france , have you some good adresse online not too expensive ?

So what about your solution to cleane cylinder head and cylinder? I find a post in an other forum with acid oxalic, it seems very good result but what about danger for motor? Anyone tested that?

 

[gentlemanjim]

Crysilic acid is what professional engine rebuiders use - if yo can find it. It is often called cold decarbonizer.

OEM Yamaha Parts availble here: http://www.boats.net/parts/search/Yamaha/Motorcycle/parts.html

 

[niko]

it's not very expnsive for you! for example for the same ringset STD (50$), in france it cost 67€ => 88,5$ !!

I don't know te shipping cost, taxes, but it may be very interesting for me to buy in USA.

I don't know what is acid crysilic in french but i'm looking for a solution not only the carbon on piston or cylinder head but for engine outside.

 

[drewpy]

have you tried www.cmsnl.com ?

 

[niko]

hello,

for my dirt track project , i'm looking for a smaller fuel tank. I d'ont know wich model could be adaptable with the 2 big ignition coil of 400xs. have you ideas? experiences?
tks

 

[gentlemanjim]

I like the look of the Yamaha Dt, At or TY, 2 stroke enduro bikes. They come in 125, 175, 250, 360 cc, I believe all with the same size tank. It should be asy to relocate the coils if necessary.

 

[niko]

yes, i like it so but it seems not easy to adapt on the 400, not only because of the coils but also because of the 2 bars on each side of the central bar of the frame. Have you some exemple about tank adaptation?

 

[drewpy]

hello,

for my dirt track project , i'm looking for a smaller fuel tank. I d'ont know wich model could be adaptable with the 2 big ignition coil of 400xs. have you ideas? experiences?
tks

ignore the coil location. you can put them somewhere else like my tracker.
DT 175 will fit with a bit of modification

 

[niko]

I think my cam chain guide are not necessarily in good condition. I heard that the 650 had a tendency to crumble. this is no longer available from Yamaha, is what some have changed? Is there an alternative?

 

[niko]

now the engine is finished:

Yesterday I tried to see the positions between the tank and the seat.
So I still hesitate about the tank. The simplest would be to keep the original but I thought it was too big. but i don't know what tank will be great, not too big and could hide the coil has the original.

finally with this test i think it's not so bad, what do you think? have you idea about tank ?

 

[OliverB]

Looks good to me! Your engine is beautiful. How did you get it to shine so much?

 

[niko]

How did you get it to shine so much?

the picture is good!
the light is good!


my method:

degreasing, cleaning brush, and brushing with the steel brush with dremel and for the down engine fine brass brush on a drill.

For carters I have tried to polish! it's a reel job and not mine

it's not perferct but it's clean!