Stock should be 90/90-18 front and 110/90-18 rear. Your bike will handle the best with stock size tires.
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'79 xs400 rough>reliable>cafe 'Scarlett'
- Thread starter jthiessen
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jthiessen
XS400 Addict
Was working on my battery cables this evening, installing a longer negative wire and was planning on using the old negative to replace the positive wire to put that Hitachi piece (starter?) under my tank area. Then I saw that there was a red wire crimped into the braided battery wire.
First of all I didn't even know the battery wire was braided. I was planning on replacing both positive and negative cables with 6 gauge copper strand wire.
So my questions for the night are:
1. Can I pull the red wire out of the short braided connector and crimp it into the longer wire I am taking off of the negative terminal?
2. Will the stock negative cable be the correct gauge to run between the Hitachi piece and the battery?
3. What gauge should the new negative terminal be? I currently have a piece of 6 gauge I was planning on using.
First of all I didn't even know the battery wire was braided. I was planning on replacing both positive and negative cables with 6 gauge copper strand wire.
So my questions for the night are:
1. Can I pull the red wire out of the short braided connector and crimp it into the longer wire I am taking off of the negative terminal?
2. Will the stock negative cable be the correct gauge to run between the Hitachi piece and the battery?
3. What gauge should the new negative terminal be? I currently have a piece of 6 gauge I was planning on using.
jthiessen
XS400 Addict
Shameless bump for the above. Was planning on heading to get some supplies after work.
When using a e-starter use the same size(or bigger) wire that is already there. You can go longer length but I would not go any smaller gauge.
jthiessen
XS400 Addict
So I wanted to go for a ride today, but when I hit the starter it just turned and turned. I tried a few times. I gave it throttle, had choke on. But it just spun and had a few sputs but didn't catch.
It eventually did catch but the idle was very low. I adjusted that and it seemed to hold around 2k decently.
I let it warm up a bit and turn off the choke.
When I put it in gear and tried to take off I had to have the throttle wide open to keep it from stalling, and even with that my RPM was at ~900 and the bike slowly moved forward.
Once I was rolling a bit more the RPM would kick up to a seeming normal rate and the bike would ride fine, but when I came to a red light the same thing happened.
Needless to say I cut the ride very short.
Last time I rode it the bike was great, not perfect but a helluva lot better than this. The only thing I adjusted between rides was adding different cables to that Hitachi piece...
What is going on here? I'm assuming I'm going to be told to look at the carbs, so what should I be looking for/at?
It eventually did catch but the idle was very low. I adjusted that and it seemed to hold around 2k decently.
I let it warm up a bit and turn off the choke.
When I put it in gear and tried to take off I had to have the throttle wide open to keep it from stalling, and even with that my RPM was at ~900 and the bike slowly moved forward.
Once I was rolling a bit more the RPM would kick up to a seeming normal rate and the bike would ride fine, but when I came to a red light the same thing happened.
Needless to say I cut the ride very short.
Last time I rode it the bike was great, not perfect but a helluva lot better than this. The only thing I adjusted between rides was adding different cables to that Hitachi piece...
What is going on here? I'm assuming I'm going to be told to look at the carbs, so what should I be looking for/at?
If all you changed with wires you may be getting a weak spark. Look at the plugs and see how they look. Then check them for spark. They should have a bright blue spark.
jthiessen
XS400 Addict
So, I went to check the quality of my spark today and pulled out these bad boys:
The right (from right cylinder) was wet with fuel which is saying something cause I haven't ridden it for 3 days. The left had a bit of silver still on the tip, the rest was black.
Would these spark plugs be the reason for my poor running (as stated above)?
I've got pod filters on H-pipe and all I've done is set my air mixture screws 3 turns out, the rest of my carbs are stock.
PS I am afraid my left spark plug had been cross threaded by a friend...
The right (from right cylinder) was wet with fuel which is saying something cause I haven't ridden it for 3 days. The left had a bit of silver still on the tip, the rest was black.
Would these spark plugs be the reason for my poor running (as stated above)?
I've got pod filters on H-pipe and all I've done is set my air mixture screws 3 turns out, the rest of my carbs are stock.
PS I am afraid my left spark plug had been cross threaded by a friend...
What number plugs are those? You should have a bp7es in there or a bpr7eix if you are running non-resistor caps.
jthiessen
XS400 Addict
Running BPR7ES
The plugs you just posted look to have an 8 on them
jthiessen
XS400 Addict
The plugs you just posted look to have an 8 on them
Ah, yes they do. Now I remember, those are what the PO had put in. I've since bought the 7's but haven't put them in yet. I will now.
But as for the adjustments I should be making to the carbs?
When you run the bpr7es plugs make sure that your plug caps are non-resistor it will make a difference. Also do a plug check after a good 50 mile run at highway speeds. Making short low speed runs will not give you a good reading.
smurfy71
XS400 Addict
I just put the K657 on my bike, although I haven't ridden on the road with it yet, the sidewall is similar to the Bridgestone Spitfire which I have used before. If you go over that far, that you run out of tread, bravo. I actually think it is designed that way to provide more tire contact with the road.
jthiessen
XS400 Addict
I put new spark plugs in and give the air mixture screws 1 turn in.
For now the boggy acceleration issue is gone and the bike is pretty responsive. However I have a hovering/lingering idle issue when I come to a stop, judging from the searches/readings one full turn in of the air mixture screws may have been too much?
Next ride I will adjust it 1/4 turn out and see how that helps. I just don't want to run into the overly rich issue I had previously.
For now the boggy acceleration issue is gone and the bike is pretty responsive. However I have a hovering/lingering idle issue when I come to a stop, judging from the searches/readings one full turn in of the air mixture screws may have been too much?
Next ride I will adjust it 1/4 turn out and see how that helps. I just don't want to run into the overly rich issue I had previously.
Have you synced the carbs yet?
jthiessen
XS400 Addict
I don't think I have since I did my valves last.
iamunique127
XS360C Owner
I can't tell you how helpful this comment is, xschris. You say those few words to so many ppl and it is frequently what is needed.
Personally, I didn't know how important syncing carbs could be. You asked me the same question and I was hesitant to attempt syncing my carbs. I finally went ahead and built a mammogram and that was the hardest part of the job. Syncing is easy and cleared up my idle issues.
On behalf of the community, thanks xschris!
Thank you. Most often the simple fix is all we need. A few years ago I told a guy I was riding with this and he said he benched synced them at that is all he needed. I said nope so we went to my house and I synced the bike with my mercury stix. The bike run better than it ever had. The guy was very happy and amazed
DARKMIDKNIGHTWARRIOR
XS400 Addict
You built a mammogram? Awesome!! LOL
jthiessen
XS400 Addict
Haven't posted for a while now, figure I would give an update...even though there is not much to report. But I can recap this almost past year!
Its been about 10 months owning this bike. My very first street bike. I originally purchased it to use as a second driver during the summer months, but I ended up cutting into the bike, I haven't got it fully together and dialled in yet. Partially lack of time, partially lack of skills, but mostly lack of funds. (you can't spell 'funds' with out 'fun' which is ironic, because you first need funds before you have fun...well, you get the picture).
My original plans for this bike were very simple; lower bars maybe a paint job on the tank, but keep it simple for now, then maybe customize it more down the road. Then I came across this forum and those plans went out the window. Seeing bikes like xschris' Clementine, Drewpy's 333 Speedshit and the many more had really inspired me to get creative. Plus this forum has been remarkable in how supportive it is! (And my wife said I was allowed to 'go to town' so that never hurts!) I doodled and dreamed and came up Scarlett - a bike that has some hips, a touch of blonde and overall dead sexy.
The bike was originally stored at my in-laws about an hour from my house, resulting in me having to plan my days far in advance. But it was a warm, safe garage with lots of tools. Then my in-laws decided to build a cabin in the woods and rent out their house. Then my bike moved to my sisters carport at her house. I managed to work the brakes and a few other things, but I knew it wouldn't stay there for long. So after that I brought it home to sit in my parking stall in front of my Jetta. It wasn't ideal, but so far it's been safe!
I set my valves, cleaned my carbs (three times) and tinkered and tinkered. Unfortunately, I just didn't have the depth of knowledge needed to make this bike run great. First its too rich, then to lean. RPM linger off throttle, engine dies off choke. This and that again and again. This weekend I am bringing it to a good mechanic to have some new rubber put on and I hope he will have some advice to get the bike running perfect...for next season.
Once I the new tires on, I hereby close phase one of Scarlett. I will winterize the bike and store it safely for the harsh seasons ahead. But like a phoenix from the ashes I am determined to have this bike run like a triathlete and look like a supermodel. It will happen!!
I will keep working slowly on this and that during the winter, but I think I need a free-time cash muting hiatus...
The day I got her:
How she sits now:
Thanks to the forum for all the help!
Its been about 10 months owning this bike. My very first street bike. I originally purchased it to use as a second driver during the summer months, but I ended up cutting into the bike, I haven't got it fully together and dialled in yet. Partially lack of time, partially lack of skills, but mostly lack of funds. (you can't spell 'funds' with out 'fun' which is ironic, because you first need funds before you have fun...well, you get the picture).
My original plans for this bike were very simple; lower bars maybe a paint job on the tank, but keep it simple for now, then maybe customize it more down the road. Then I came across this forum and those plans went out the window. Seeing bikes like xschris' Clementine, Drewpy's 333 Speedshit and the many more had really inspired me to get creative. Plus this forum has been remarkable in how supportive it is! (And my wife said I was allowed to 'go to town' so that never hurts!) I doodled and dreamed and came up Scarlett - a bike that has some hips, a touch of blonde and overall dead sexy.
The bike was originally stored at my in-laws about an hour from my house, resulting in me having to plan my days far in advance. But it was a warm, safe garage with lots of tools. Then my in-laws decided to build a cabin in the woods and rent out their house. Then my bike moved to my sisters carport at her house. I managed to work the brakes and a few other things, but I knew it wouldn't stay there for long. So after that I brought it home to sit in my parking stall in front of my Jetta. It wasn't ideal, but so far it's been safe!
I set my valves, cleaned my carbs (three times) and tinkered and tinkered. Unfortunately, I just didn't have the depth of knowledge needed to make this bike run great. First its too rich, then to lean. RPM linger off throttle, engine dies off choke. This and that again and again. This weekend I am bringing it to a good mechanic to have some new rubber put on and I hope he will have some advice to get the bike running perfect...for next season.
Once I the new tires on, I hereby close phase one of Scarlett. I will winterize the bike and store it safely for the harsh seasons ahead. But like a phoenix from the ashes I am determined to have this bike run like a triathlete and look like a supermodel. It will happen!!
I will keep working slowly on this and that during the winter, but I think I need a free-time cash muting hiatus...
The day I got her:
How she sits now:
Thanks to the forum for all the help!
