New to Seca400

Philip Gour

XS400 Member
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Hello all,
Picked up an 82 Seca400 recently. Spent the time to rebuild the carbs including new shaft seals, jets, float needles and did a thorough cleaning with an ultra sound bath. Unfortunately the last owner turned the air box into modern art and had to switch to air pods. The bike definitely ran last in 2019. With the carbs installed, hit the starter and engine ran at idle speed but would NOT rev up and quickly dies. At this point I’m not even sure that I’m getting any oil pressure so I thought I would ask questions before I go any further.
1. Do I need to up the jet sizes due to the air pods?
2. If so, what jets sizes might be appropriate?
3. Is there a way to determine if I’m getting oil pressure besides the dash light?
Thanks to all
I think it is too soon to jump to changing jets as there is still some things to look at first.
1. Look at the inside of your pods - do they block any of the air openings around the intake side of the carb?
2. Do you know if you are getting good fuel flow from your petcock. Those vacuum petcocks sometimes fail and not open fully.

Regarding the oil pressure indication, there is no place to easily look for oil flow (that's one of the reasons that Japanese bikes have a reputation for not leaking). I would do the following:
1. Check the bulb and the bulb holder ground connection.
2. Check wire continuity from the oil sender to the bulb.
3. If those things are okay, pull the sender and take it to your nearest auto parts store and have them give you a new one to put in.
Thanks for the quick reply. I pulled the pods and verified that they do not obstruct any part of the intake side of the carbs. Also I was using a bench tank and had sealed off the vacuum port on the left intake port.
When I did the rebuild, I noticed that the manual notes two different sized mains, left127.5 and right 117.5. So I made sure that the rebuild kit had these sizes. Is this correct? Seems strange to have two different sizes. Is it possibly because the vacuum petcock runs off the left intake. Should I change both mains to the 117.5 if I have the vacuum sealed?

thanks again for the prompt reply
I have an '82 Seca, docs also detail the assymetric jetting, as I've heard it the left one is jetted more open because it gets more air from the OEM airbox- not sure I buy that. But my bike as the OEM airbox so I drilled out my left jet to match the spec but it didn't make any observable difference- I'd leave them the same since you're using pods.

The left port should be capped or connected to the vacuum operated petcock, the right carb's port should be capped.
Hey there I have an 83’ SECA. Starting to get into a few part swaps, gauge cluster (need to find a wiring manual), new levers, integrated tail light, Matt black front indicators.

My big question that I’m having trouble starting my plan is with a fork swap. I’m looking to go with a 50/50 scrambler build. Any tips on where I can start to figure what forks are compatible for off-road use.