82 Seca Turbo Build

I joined the site recently and have spent lots of time reading. As a side business I rebuild 70-80 UJM bikes for resale.

This will be primarily a pictorial as I go through and rebuild or replace what is needed.

Recently I found a 1982 XJ650LJ.

Phone pic sorry

Bike is low mileage, and has not been running in several months due to needing carb work.

I don't have the time or the room in the shop for it at the moment but, I went ahead and pulled the gas tank to drain it. It was full and was just starting to smell bad. No rust inside the tank either!

While I was pulling the tank, I noticed the battery was still there and disconnected. Upon further inspection I found that it's an AGM battery with a FULL charge! I hooked it up, turned the key, and the dash lit up. All lights and accessories seem to work just fine.

Also, I noticed the exhaust is in excellent condition with no rust in the typical places. I am starting to think that this bike was well cared for by it's previous owners, with the exception of some broken faring tabs, a turn signal lens, and faded wind screen it's in good shape.

I will need some parts, for starters I'll need the carb to surge tank boots, and tank to air filter box boots. There is some oil residue under the turbo that might indicate leaking seals. With only 7300 miles on the clock, I'd like to think the seals are still good but we'll see.

I happened to find a NOS front turn signal lens and a Canadian gauge cluster with the 240kph / 150mph markings today!! I really dislike the whole 85mph speedos of the early 80's!

Randy

 

Welcome to the site ! Is that 3 new Turbo guys this week??
Yours sounds almost ready to ride. Check your rear brakes.

 

I posted an introduction thread last week also. I didn't have the bike home at the time though. Brakes will be replaced all around and braided stainless lines will go up front. It's missing the master cylinder so that will be an upgrade.

 

Last night I had a chance to pull the carbs off and open them up. Everything looked pretty good. They had recently been dipped and had very little gas in the bowls. The gas had already turned sour but hadn't started turning into shellac.

The mechanic I purchased the bike from destroyed the carb to surge tank boots, ( along with setting the idle mix screws anywhere from 1.5 - 4.5 turns out!!) so I needed new ones.

Don't really want to shell out for Yamaha parts, if you can even get them for a turbo bike anymore, so I dug around in the shop. I found some 1.5" x 1.5" rubber plumbing couplers.


Did some measuring, and figured cutting them into 30mm lengths would be perfect. I figured for the width of the blade of my bandsaw and started cutting.


Came out exactly the same height as the stock boot I was able to get two boots out of each coupler. Since I didn't have the stock clamps anymore I used some stainless hose clamps. I think this works out better since the stainless clamps are wider than the stockers.






I did take the dremel with a drum sander and shave down the high sides to match the groove that the original hose clamp resides in.



These should be plenty strong enough to handle the puny amounts of boost the stock turbo puts out.

 

Nice work. Did you get the couplings from Lowe's or Home Depot? I got mine from Lowe's when I was attempting to make a PVC manifold.

 

Thanks. I got them from lowe's. How did the PVC manifold come out? I may have to do something there too, the guy was really rough when he tried putting the carbs in and tore up most of the fittings. The manifolds seem ok, but I haven't pulled and inspected them yet.

 

Thanks. I got them from lowe's. How did the PVC manifold come out? I may have to do something there too, the guy was really rough when he tried putting the carbs in and tore up most of the fittings. The manifolds seem ok, but I haven't pulled and inspected them yet.

 

Well I made two of which I never got to use. I made one out of 1inch and 1 out of 1-1/2 inch but the carbs needed some serious cleaning first. Then I found out that I had the wrong set of carbs(32's instead of 33's), since I needed another set of carbs I decided to go with some flatslide carbs with velocity stacks. :wink: Just waiting on the funds.

 

Got a chance to do a compression test today. Readings as follows"

#1 - 135 psi
#2 - 135 psi
#3 - 140 psi
#4 - 145 psi

waiting on service manual, so I don't know yet if these #'s are good or bad. Anyone know off the top of their head?

The plugs seem a little oily, but mostly black with carbon, and the collector and turbo are covered in oil buildup. The turbo will get a rebuild, maybe valve seals too. I'll get the carbs back together, fresh oil, gas, and fire it up.

 

I did the same with my GS750 build, and ditched the stock CV carbs for some bored GSXR flatslides from a 86 euro spec bike. Never looked back, those Mikuni flatslides are the shit!