armyofda12mnkeys

12v10w is right... but they don't have the 'right' version . So what would happen if i put that 14.4V 1.8W* in instead? Would it try to suck more juice causing problems or just be dim.

curious my bike's turn signals have single filament 12v 10w lights in them. Pep Boys only has 14.4V 1.8W lights... Will these work out?

hah i guess MikesXS does have everything. This was first time i saw a part i thoiught they didnt havve Thanks!

Hello all, I'm looking for the lil screw-in jet on the left side on the back of the carb. I think its different than the 'pilot jet' which is inside the carb.... This is called the 'air pilot jet'. I think the values on that hole are 170 when i looked at it (but on backup carb i have I think i saw 155), not sure whats stock. I think the 'air pilot jet' is #52 here (vs #12 for the 'pilot jet'): http://www.boats.net/parts/search/Yamaha/Motorcycle/1978/XS400E/CARBURETOR/parts.html I think my is a bit stripped so i was looking to replace. MikesXS has 'pilot jets' but i didnt see 'air pilot jets' Thanks!, -Arian

PS is this the missing washer you thought wasnt there drewpy? Its recessed into the carb main jet hole on both sides. Seems like should be there? So its under the Main jet screw... but i guess you were talking about the other screw in first pic i posted (aka #13 in diagram vs #10 which is Main jet screw) Anyway let me know if i still need a washer under that screw .

thanks! I forgot about MikesXS BS34 parts . I have an extra carb I'll use as a backup from a 77 thats just as nice. Ive opened it a few times with no problem with the float gaskets as they are pretty thick/tough. My electric ignition xs400 cafe racer ran well the first year, thanks again to kmac and drewpy for helping. Im gonna maybe ask someone to weld some custom brackets for some new Dyna Coils i bought, as kmac figured the correct coils to use and seemed to run well.

cool , where do you buy the washer? i saw it discontinued if its item #11 on diagram: http://www.boats.net/parts/search/Yamaha/Motorcycle/1978/XS400E/CARBURETOR/parts.html

hah, interesting.. would there be any side effects of a missing washer during bike operation? Also would you suggest removing the black round gasket? it was on both 1978 XS400 carbs, but then again you have the same bike I remembered, so If you dont have it and the bike is fine. Then I can get rid of it i guess -Arian

Just curious, i lost one of the rubber 'round' gasket part that goes behind the Float Gasket... Pic attached... I didnt see it anywhere on yamaha's offical parts: http://www.boats.net/parts/search/Yamaha/Motorcycle/1978/XS400E/CARBURETOR/parts.html Is this part terribly important and if so, where do I buy it ?

>have you changed the idle jets didnt change the idle jet, didnt think the air filter was that crazy of a mod that it can't at least run 80% of its former glory and idle fine. I did see DimeCityCycles has 2 sizes for these cb idle jets. I could get one i suppose but i doubt thats issue. it was kinda running the same way before upgraded air filters/cleaned carbs >it could be the carbs haven't been cleaned properly. hmmm i cleaned the carbs i thought well, maybe i'll take another look. what specifically would cause that pocket of air to be forced backwards like that?

I asked on dotheton, but just thought I'd ask here too since Yamaha folks have always been great. My friends '74 cb450 had a variety of issues. I had to clean his carbs as his bike started to run bad, and he let it sit for too long which gunked up carbs. We then put on uni-filters since his stock air filters were breaking up, and we put a higher main jet for that air filter. Bike starts after 5-10 kicks, but stumbles/splutters. Idle mixture doesn't seem to help at all. Bikes symptons are: 1. Backfires occasionally out of right exhaust. Sounds like a gunshot hehe. (read that lean or rich conditions can cause it, but idle mixture seems to be fine). 2. Has a noise coming out of right air filter. We took off air filter and see some air is pushed back to air filter (splats a lil' gas droplets back if you put your hand there). 3. While engine is weak at startup, if you give it some throttle it may not cut off... if so, after riding for 5m, it may have high idle. Bike rides decent in 3rd gear giving throttle, but at the lights, it stays at 3k rpms. I am guessing timing? like maybe intake opens at wrong time and forces air into carb?, and exhaust opens at wrong time, causing un-ignited gas to hit the hot exhaust and ignited there? Exhaust is hot, so gas is ignited most of the time it seems though. Used a Colortune sparkplug to confirm that gas is igniting on that side (didnt pay attention though if it was missing ignition during those exhaust-gunshot or carb-intake sounds).

I saw one video where they had wires going around each prong/input on the relay (of a car), and then they plugged it in (so each wire still stuck out and could be tested). And then he tested each of the wires for continuity... Would this pretty much be the same for testing my relay? For voltage drop testing... should each of those prongs be tested (3 prongs on the flasher relay), or only one is really needed to test?

well i think theres a way to specifically test the specific device you want (my flasher relay) ... vs just reading the battery. I'll figure it out in next few days, got a book on voltage testing. Anyway the values of just the battery were as follows: (ps bike never actually started, just ignition turned on (no engine) in following tests) motorcycle off: 12.78v (seemed to rise slowly from 12.74 over next minute) motorcycle key ignition on (light off): 12.45v motorcycle key ignition on (light off) + put kill-switch to Run: drops to 12.35v and bounces back up to 12.45v motorcycle key ignition on + put kill-switch to Run + turn light on: 12.33v motorcycle key ignition on + put kill-switch to Run + turn light on + turn on left signal: 12.31 cancel signal: then goes back to around 12.32 motorcycle key ignition on + put kill-switch to Run + turn light on + turn on right signal: 12.31 cancel signal: then goes back to around 12.32 think above test didnt help much.... need to test if that device itself is getting all the power it needs? it may just lose resistance through a frayed cable and you wouldn't know about it unless u tested that device right, as the other devices in parallel will use up their 12v and return 0 back to ground, and wouldnt neccessarily know about that flasher unit? think i need to test positive side of that unit, aka hook positive to positive of battery and negative to one? of wires the input of the flasher relay unit. and then test the ground side to make sure it used up almost all the Volts it was given.

I wanted to just test and see if my turn signal flasher unit on my 78 XS400 is getting the power it needs. I was reading about voltage drop testing ... How can I voltage drop test this device? ... Do you have to cut into the wire going into it and out of it to measure it, or can you somehow do it without cutting into the wires (i assume so)? Thanks for any advice

Hey Guys, I was taking my spark plug out to read what color it was after having it running for a few minutes ... and when i pull the plug out, I see some smoke lightly come out for next minute or so... just a light white smoke gently streaming out. But I never seen anything ever come out of the plug hole when I took out my plugs to read them (and Ive done this about a 100 times). Just curious what it could mean ... I probably still have some SeaFoam left in the gas if you think it could be SeaFoam 'burning' off hehe. -Arian

I know this is a repeat of previous threads... but not sure if my problem is different so thought I'd post... My bike has been riding great past 2 weeks... Couple days ago, I put 3oz of SeaFoam to my tank which had 3 gallons of gas probably and road around probably .5 gallons fine... I accidentally left my manual petcock on overnight. Garage might have smelled a bit gassy yesterday, but no gas leaked out of airbox which was my main concern. Had alot of trouble starting bike so i initially thought it was too much gas getting passed floats and leaking somewhere bad ... Tried starting many times to no avail ... checked plugs. maybe one was a bit wet/gassy ... I cleared it up. Then tested the sparkplugs grounded against engine, they were firing ... I noticed if i gave it a little gas, it would start... but could't hold it. it would just cut out unlesss I lightly gave it some throttle... With no throttle, instead of usual 1200rpms, it was at 800rpms hence why it probably cut off... I raised the throttle stop today, and I thought it helped as the bike would not cut out at idle ... but noticed at redlights, the idle would stick high around 3000rpms and not come down... Unless i pulled the choke out and pushed it back in quick heh. But high idle would just come back at next redlight. I'll probably mess with the idle mixture and throttle stop later today. Just thought I'd ask... I dunno maybe my previous tuning was for an engine without cleared valves? (assuming SeaFoam musta cleaned something up hehe), and not a cleaned up engine lol... or maybe the SeaFoam is making the fuel/air mixture different (maybe more or less enriched) and maybe need to temporary set idle-mixture differently. -Arian EDIT: seemed to be alright riding it around during lunch, had to set the idle-stop lower to where it was before so rpms went back down to 1.2rpms ... Hoping it doesn't get into that 'i dont want to start without throttle' mode again.

I have heard from a few folks that letting your dented tank sit in the sun (or use blowdryer on it or apply some heat with fire? and alum foil protecting tank paint... option #1 best hehe)... Then with heavy duty gloves suitable for dry ice... to take some dry ice and apply it to the dent... Hold it down for a lil' and it'll pop out as long as dent isn't a 'hard dent' (has hard creases): http://www.ehow.com/how_6620077_remove-dent-motorcycle-gas-tank.html http://www.videojug.com/film/dent-removal-technique btw nice technique, ill have to remember that in case ever need.

Hmmm, sorry I think I'm going to keep it to swap looks occasionally. I think it may just be an old Mac 2-1 exhaust though easy to find on ebay. Here is a nice looking one that Im not sure is Mac... (People say the Mac pipes are awful anyway) http://cgi.ebay.com/ebaymotors/1980-Yamaha-XS400-XS-Chrome-2-into-1-Compete-Exhaust-_W0QQcmdZViewItemQQitemZ120602251918QQptZMotorcyclesQ5fPartsQ5fAccessories

I was curious. I had an old non-stock 2-1 exhaust on my bike when I bought it. Im going to convert back to 2-2... I already bought some nice mufflers and then asked around for some headers... Got a nice 81 exhaust almost free from someone. Not sure if its stock... The mufflers seemed to be welded on the headers ... Will get a local shop to nicely cut 'em off. My question is... it looks like the exhaust has a pipe underneath that connects them both to each other... What is the purpose of this? Can i just get away with putting on my mufflers onto the headers and not doing a shared exhaust system? Thanks!, Arian

Any of these also match your bike?: http://craiglook.com/all.html?q=R6+headlight

Yes it works very well. i tried reading spark plugs but never got it as good as close as with the Colortune. Also it helped confirm my friends Honda CB450 problem last week. His bike was having hard time to start (20 kicks!) and even then cut off often before we could even ride it... Apparently cyclinder wasn't getting any gas. and we wouldnt have known with our basic skills as he had a 2-1 exhaust so we couldnt feel exhaust pressure. We were testing spark before by grounding against engine and were stumped as it had good spark... also spark plug may have been fouled once with gas on it so we thought it was getting gas good ... colortune revealed spark but no ignition .... and we look at the right carb and found it had white chalky (old gas?). so the float needle was sticking 95% of the time (except that one time we saw gas) and not getting any gas to cylinder. I guess we could have also just felt the header and see if it was warm. Im cleaning carbs for him now, so hopefully that'll run soon too and buddies can ride together PS oh yeh when i got it started in the video, my dad heard and came in pretty excited to congratulate me. He's been busting my chops for months that I'm no mechanic and can't do it, and should to just my main profession lol. He thought it was gonna blow up on me haha. Gave me more motivation .

haha I like the bare look of the air boxes without the side covers . Bought some of the pod lookin ones off ebay but eh, wasnt a fan plus didnt want to re-jet (plus they didnt fit! err all the xs400 pod filters on ebay claim they fit, but they dont. mine are 54mm and those are all 48mm).... i SHOULD polish the air filter cases . They look a bit shiny in the middle cause are taped up lol cause the screws were stripped and not holding them together.... In fact 1hr after this pic, i found someone on craigslist who came over and traded a new air boxes + mufflers + headers for an old pair of side covers i had (GOOD TRADE 4 me)... Yeh i thought i may try it in future... do 81 xs400 wire wheels swap into a 78 x400? Id love to have this old time look:

wowie nice rebuild! Here is google's translation of the rebuild if anyone wants to follow along his work (re-looking at the webpage ... doesnt show the pics btw, darn moto-forums.nl website must be past their bandwidth): Dutch to English translation First small question: just curious are those MikesXS fork gaiters? some peeps told me the 650 forks are bigger so they wont fit. I have an xs400 myself... Do you know if the 77' tank fits an XS650? i have a 78 xs400 that has a fiberglass tank that is made for xs650 tank mounts (rewelded front mounts). so if it fits an xs650, it'll fit mine lol.

cool, if you can see now, it is just has zip-tied-downs onto the frame lol... but its not really grounded as its the rubber part and not metal on metal i think... She's running fine. but i'll probably add a ground wire jussst in case soon. New look:

Hey drewp, The smoke looked to be the electrical tape burning off ... I used tweezers to pull it off the flanges and it stopped smokin g(i had tape on their in first place cause it took 30m trying to put exhaust on myself and the flanges kept slipping off, so i got pissed and decided to just use small tape to hold them together on the headers while sliding them in and accidentally left them on). I used a Colortune today on the carbs just to get the mixture right, and got the bike works perfectly! I dunno what i would do without a Colortune. The electronic ignition is running great! it took a few weeks confirming the wiring... 1.5 months total as i wanted to take off the old 78 engine/carbs and go through my manual learning about basics. I wanna thank kmac for helping me out so much! I'm basically following his work, and I just decided i want to put Dyna coils on there, and who is the first match on google for dyna ignition coils xs400: yamahaclub thread by kmac... so DC3-2 coils have 3ohm resistance like electronic ignition has so he tried it and it works. Thats the next project . ... [ and maybe adding new mufflers and paint the tank ]