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What did you do with your XS today?
- Thread starter logan
- Start date
My engine started sounding like it had low oil pressure, so I changed it for the spare Seca engine I had bought in the fall.
Time for a test ride to see how well it runs and how the 6 gears are spaced.
Time for a test ride to see how well it runs and how the 6 gears are spaced.
You did what? When?
It sounded okay the other day, you sure you weren't just looking for a good sounding excuse?
I'm interested to find out how the Seca motor works.
Some time ago, I was led to believe that the overall final ratio in top gear was the same with a Seca, however, you will be mixing the Seca gear ratio and front sprocket with a Maxim rear sprocket and rear tire. I tried to do all the math, but I also seem to recall you fooling around with sprockets too - so any of my calculations will be off.
It sounded okay the other day, you sure you weren't just looking for a good sounding excuse?
I'm interested to find out how the Seca motor works.
Some time ago, I was led to believe that the overall final ratio in top gear was the same with a Seca, however, you will be mixing the Seca gear ratio and front sprocket with a Maxim rear sprocket and rear tire. I tried to do all the math, but I also seem to recall you fooling around with sprockets too - so any of my calculations will be off.
Started the swap late yesterday afternoon, finished about an hour ago. I had reason to change the engine. It decided to loose oil pressure at an idle the other day. That sealed it's fate.
I've been running a Seca rear sprocket for over a year, in combination with a 17t front. That combo had the engine revving slightly higher than a stock Maxim. It will be interesting to se how the Seca 6 speed transmission gearing compares.
I've been running a Seca rear sprocket for over a year, in combination with a 17t front. That combo had the engine revving slightly higher than a stock Maxim. It will be interesting to se how the Seca 6 speed transmission gearing compares.
So you think the crank bearings are gone now? Will you open it up for a rebuild? How many miles on the seca motor?
Sounds like it. I know the intake cam was wearing after a valve adjusting shim exploded a couple years ago (I kinda may have possibly over revved the engine once in anger). And I have laid it on it's side a couple times while off road. No plans on rebuilding the old engine at this time, but it will be kept for spare parts.
The Seca motor is a complete unknown. I paid $50 for it because it wouldn't fully turn over by hand. Found the cams were timed wrong and corrected that. Did a cold leak down test and both cylinders were at or below 5% leakage, the lowest reading on my tester Up to 40% is considered acceptable. Figured I'd take my chances and install it.
I just completed the first real test run and had to reduce the idle speed 1/2 a turn from what the old motor needed and lean out the Pilot screws. Other than that, she runs well, is mechanically quiet, charging system is good, clutch is smooth, and all the gears are easy to select. The engine certainly isn't pretty, but I'm confidant about riding tomorrow for work. Will give it an oil change after a couple days riding. And try to make it look nicer as time permits.
SussexSlammer
XS400 Addict
Contemplated the existence of life and paint schemes.
Got the 80 sg out yesterday and put about 100 miles on it. I love that I put the e-start back in it. It ran great but at the end it started to act like it was flooding on one side. I had a bad float last year so I thought it was that. So I figured that was on my list of things to do today. The first thing I did was to replace to 2-1 because the muffler had a crack in it and I was tired of messing with this system. I put a mac 2-2 mufflers on a set of 78 xs400 head pipes. I had to weld a few tab on the bike to mount everything as I was stupid a few years ago when I cut the stock ones off.
I do have a set of stock 81-82 frame brackets that I could have used but it would have been a pain to mount. After doing that the bike started a ran fine. But a10 miles later same issue with flooding carbs sound. I checked carbs, plugs, coils and nothing was bad. So I figured may be TCI box. It was out of some other bike with I don't know how many miles that had been in my bike for three years. I put the one that came out of it that only had 11k miles on it and boom it ran perfect!
So the one I paid $15 for three years ago crapped out.
But I am not worried about running out of these things I have five others and one N.O.S one still in the box. I did have to duct tape the replacement one to the side of the bike as it is a pain to get to the bad one. 
I think I will leave it there for a while.
I do have a set of stock 81-82 frame brackets that I could have used but it would have been a pain to mount. After doing that the bike started a ran fine. But a10 miles later same issue with flooding carbs sound. I checked carbs, plugs, coils and nothing was bad. So I figured may be TCI box. It was out of some other bike with I don't know how many miles that had been in my bike for three years. I put the one that came out of it that only had 11k miles on it and boom it ran perfect!
So the one I paid $15 for three years ago crapped out.
But I am not worried about running out of these things I have five others and one N.O.S one still in the box. I did have to duct tape the replacement one to the side of the bike as it is a pain to get to the bad one. I think I will leave it there for a while.I have changed drive chain, Drove it to new place, now to clean it up, oil change.
How do you like it so far?...does the lighter crank and extra gear give a little more pep or not...curious as my Seca engine is in the bike but has not been fired as of yet...
Only street riding so far. The lighter crank has taken some getting used to. The throttle response is much more direct, so I'm having to pay more attention when starting from a standstill, and to achieve smooth shifts. More vibration is felt at idle, but not horrible. Acceleration and engine braking are noticeably more aggressive compared to the Maxim engine, even with the 17T sprocket I currently have installed. 6th gear is great for the highway or cruising, but not useable in the hills or with a strong head wind. I'm certainly doing more shifting! I'm going to do some careful measuring to see if I can drop down to the stock 16T sprocket to raise the RPM's up to stock. That should also help when I'm in the dirt, I hope!
Overall I'm pleased.
Pretty happy to hear this, as i have driven around with the Maxim last year and have never driven the Seca...looking forward to trying it out...in your opinion would a 15T front sprocket be too much.
As i've said...I want it peppy but it could quickly become "jerky"...
As i've said...I want it peppy but it could quickly become "jerky"...
If you're not planning on long rides, or spending much time at highway speeds, a 15T would probably make the the bike a blast! The word 'hooligan' comes to mind when I think of how the bike would accelerate.
I rode to a vintage bike swap meet first thing this morning, but found nothing of interest. Then to the spring open house of the shop I buy most of my parts from. Honda had demo bikes available so I test rode a CB500X (nice bike If a bit small for me), a modified CB500X (
) and an NC750 with DCT ( 
). Riding my bike home still put a smile on my face, so I decided I'd keep it and changed it's oil to show my devotion.
I rode to a vintage bike swap meet first thing this morning, but found nothing of interest. Then to the spring open house of the shop I buy most of my parts from. Honda had demo bikes available so I test rode a CB500X (nice bike If a bit small for me), a modified CB500X (
) and an NC750 with DCT ( ). Riding my bike home still put a smile on my face, so I decided I'd keep it and changed it's oil to show my devotion.
Stock would be 110/90 for the rear.I got new Avon AM26 Road Riders! 100/90-18 rear and 90/90/18 front.
Tate
Knowledge speaks,but wisdom listens
Nice to see your bike back together again Tate!
I changed out my auxiliary flood lamps for a pair of spot lamps. I want to be able to see further down the road at night. Waiting for the sun to set so I can do the final aiming.
I changed out my auxiliary flood lamps for a pair of spot lamps. I want to be able to see further down the road at night. Waiting for the sun to set so I can do the final aiming.
