Fast Taker Secaha - a blog

Hey fellas! The name's Erman, and I've just gotten myself a 1984 XJ750 Seca. I've been looking around the forums, and thought it was high-time to join.

Short intro here and I have lots of questions that will pop up in the days to come..

 

Re: New guy in town

Welcome to the forum. Great people here with a lot of knowledge. Post some pictures of your bike we'd love to see them.

 

Re: New guy in town

WELCOME from TN!!!

skillet

 

Re: New guy in town

Welcome aboard Erman!

 

Re: New guy in town

This reminds me of something that came up with a friend of mine that got an 82 Seca 750 not too long ago. The seller said it was an '84 XJ750RH and neither of us could find anywhere saying that such an animal was ever made that year. He checked the vin and found it was an made in 82. What gives?
My best guess about this situation (assuming a lack of previous owner(s) misunderstanding) is that old stock was left in a warehouse and wasn't shipped overseas and thus issued a title until later. Is there some part of the fascinating vehicle history that I would like to hear?

Oh and Welcome to the addiction Erman

 

Re: New guy in town

i thought the XJ750RH was an '81. or, more precisely, i thought my '81 was an XJ750RH . . .

 

Re: New guy in town

The years confuse me too. The guy I got it from says it's a 1984 model, but the short VIN gets me to 1982 (11M). I gather this may have something to do with the bike sitting in-store until it was first-time registrered in 1984.

Oh btw, pics will be posted once they're ready :wink:

I'm using the bike for the purpose of training for the driver's licence. I was thinking about riding it for a year or two, then sell/swap it for a cruiser. Needless to say it didn't take long before this baby grew on me.
I'm new to MCs and wrenching, so all things not "normal" on the bike are considered to be "character traits" until I get them sorted. And according to that wording, I guess you could say that my bike is quite tempered.

So, here are some things I consider "not normal" on the bike, and I would like them explained / fixed. If you guys have any tips about parts etc., feel free to

- Changing the handlebars for heated ones

- There seams to be a "sweating" from the centre of the engine, right behind the oil cooler (and possibly from the overlapping engine parts on the leftmost cylinder)

- The gas handle needs to be fastened. I'm guessing the wire here

- The tach is going wild at speeds over 100 km/h (60 mp/h). I'm guessing maybe the bearings inside are worn

- Onward from 2nd gear, the bike coughs below 2000 rpm. Shifting down resolves the problem (something to do with the carbs maybe?)

 

Re: New guy in town

all the manuals and yamaha info I find on them indicate the 750RH was made from 81-83.

Erman,
#1, beats me, new tires one out in my budget last fall and nobody got me any for x-mas. In general my friends tell me heated gloves work better and they're easier to take with you to another bike on down the road. Only one guy I know prefers heated grips for the convenience factor but he does admit they're not quite enough on some of our colder days here in the pacific northwet.

#2 I assume by sweating you mean oil leaking from the valve cover gasket. This is common. The bolts that hold down the valve cover have little rubber donuts under them that are responsible for putting just the right amount of pressure on the gasket (a nice reusable unit). These donuts (they're not quite O-rings nor are they bushings) get old and tired and hard as all rubber does. They're cheap from Chacal. The dealership will look at you funny if you ask about them then sour when you have to explain.

#3 you mean the electrical wire for all the switches?

#4 I had to dig a few generations of dead spiders out from inside my atari when I got it. Could be a lot of things causing your problem but my money is on loose or corroded connector plug somewhere.

#5 does it appear to have a stock exhaust and intake set up? whether it does or not your issue likely lies in the carbs but the answer to this is the first thing to help narrow it down for you.

 

Re: New guy in town

Welcome to the site !!
Carb cleaning may be in order- - it's like a hobby/ritual around here.

 

Re: New guy in town

Thanks for all the information guys!

I will definitely go through the holy cleansing of the carbs at one point in time

Update:
I've now gotten the throttle fixed. It was only a matter of tightening the wire by the handlebar insert. Idling at about 500RPM now.

- I spent the latter part of yesterday taking off the GIVI luggage holder that came with the bike and the seat.
- Also the plastic covers were removed and cleaned (man I wish these were made of metal... :roll: )
- All the rusty parts are sprayed with WD40.
- The bulb housings were cleaned too. I noticed two diagonal screws on the main headlight that adjust the beam elevation. Do any of you guys have a "favorite" position for this?
- When taking apart the covers, I noticed that the rubbers in between were quite worn. I guess I have to put in an order at Chakal for these?


Next up will be to clean the sweaty engine and put shine to it..
The color of the covers and the tank don't match, so I'm looking to repaint them in the ruby red color of the gas tank.
Do any of you know the correct mix for the original red color?

 

Re: New guy in town

Bump

 

Re: New guy in town

Check your tach cable. If one end is coming loose, it can cause the needle to bounce around. They need to be tightened from time to time.

 

Re: New guy in town

Thanks man, will do!

 

Re: New guy in town

So, I was out with the bike again yesterday.
I've been playing with the idle screw to get the idle to about 500-1000 RPM, and it seemed to help a little.
That is, until we got on the road. The engine was jerky below 2000 RPM before almost as if it wasn't getting enough air, but yesterday it did the same at about 2500 RPM... Maybe I opened the idle screw too much?

 

Re: New guy in town

A friend and were doing a safety check of the bike on Sunday...

I gotta say, the idle is very nice now. I just need to open the choke 1mm or so, and se purrs like a little tiger cub ;D

But there's a catch. We put it on the center stand and took it up to 1st gear, and there was a banging sound coming from what we could gather must have been the drive shaft. Once we gave it more gas and let it rest, the sound disappeared.
But it could very well be the engine/carbs that's out of sync. I've ordered one unit of Colortune to check how the engine fires...

I'll be back with more later.

 

Re: New guy in town

Erman, as long as your brakes are safe, your next area of attention would be checking your valve clearances and start planning your carb cleaning by reading the 3 long, long threads - - Church of Clean, Nine Yards, and Old School.

http://www.xjbikes.com/Forums/viewtopic ... lshit.html

http://www.xjbikes.com/Forums/viewtopic ... vious.html

http://www.xjbikes.com/Forums/viewtopic/t=14692.html

This is required reading for your Doctorate.
For now, you can do a running sync and adjust your Pilot screws to get a good color on your plugs.

 

Re: New guy in town

Thanks. Gotta take a few photos to plan things first...

 

Re: New guy in town

Went out again yesterday. The weather was very warm, and both the idle and the run went well.
A funny thing happened though. I managed to empty the tank completely on the way back, and had to switch to the reserves. I have no clue how much that is though.
Anyway, I struggled to open the tank lid and took it apart for cleaning. Turns out the springs were pretty rusty. Well, not anymore, he he he.

 

Re: New guy in town

Okay, so my first bike has been in my posession for a little over one month. Thought I'd list some of the fixes that have been done, and the ones to come.
As always, if anyone got any tips or bright ideas that would make the fizes better/easier/cheaper, you're welcome to post them =)

Done:
- Changed oil to 10W/40 synthetic (the pamphlet did not specify mineral or not), and the oil filter with gaskets
- Changed air filter
- Cleaned out the battery connectors (still some dirt on the stator/charger thingy)
- Cleaned out the tank lid (was rusted on the inside), still have to replace the rubber gasket on the inside though...
- Changed grips to sweet chromed ones
- Small fixes on the footpegs (straightening bent stuff etc.)

To be done:
- Change control cable (clutch), throttle wire, speedo wire
- Repaint to color code Brilliant Red (currently two colors; BR on the tank and a horrible burgundy color on fender+fairings)
- Put a shine to the alu. throughout
- Change clutch rings(?) and springs
- Clean and sync the carbs (ordering carbtune later this week)
- Install fuel filter
- Tighten cam timing chain (faint rattle can be heard when driving)
- Clean engine & change gaskets

 

Re: New guy in town

What's the clearance between the seat rim and tank on you guys' bikes? Mine is sitting very tight, and I suspect it may affect the amount of air coming in...

 

Re: New guy in town

The time has come...
THE test is coming up in just under 12 hours. I'm super-psyched... And very nervous.

 

Re: New guy in town

Try not to be nervous.
That just erodes your confidence.
Just go and give it your best shot.

If you are going to take the test on your Bike; let's hope a tuning issue or some other gremlin doesn't get in the way of you putting down a good test!

 

Re: New guy in town

Time to refresh an old thread, I guess...

As the snow and ice fade away and give room for bare asphalt, I can feel the throttle hand wanting to grip the handles of that sweet ol' XJ...
Carbs have been cleaned and reset, the tank is scrubbed clean on the inside (some rust was apparent), the battery is charged to full, and all parts are mounted.

Tuesday night was a blast. I had to check if the bike would start, and it did - albeit after a little tinkering.
Something with the #4 plug that just wouldn't let it fire.
I cleaned the plug, swapped it with #3, swapped plug wires with #1 and back, and finally all four exhaust baffles were hot.

Now awaiting nicer temperatures at nighttime to take her out. Can't really do that during the day because of excessive traffic around the garage...

And that leaves me to thank everyone here who has helped me along with tips and parts...

 

Re: New guy in town

I finally got the bike out for a warm-up yesterday... and did a carb sync on the end.
I noticed that there was a gas leak from the lower rack screws on carb #1... anyone know what may cause this?
I hit all rack screws with thread lock, and refastened the float bowl screws with tread lock as well.
I'm holding a button on the gaskets being worn after being worked with so much, but I'm open to suggestions from you guys...

 

The bike is parked for this season (in Norway, the season officially ends September 30th)...
I dare not ride the bike anymore, mainly due to the possibility of overnight frost.
Instead, I opted to put her back in her Secave (get it? )...
I also decided to turn my original thread into a blog, so as to get everything into one post. Makes searching easier - at least for me...

Plans for the winter? Total overhaul.
During this season I've noticed a few things that I knew were missing from the PO, and some things that came after me riding the bike for 8000 km...

- Sweating from the engine gaskets
- Adjusting the headlight beam
- Holes in the exhaust collector
- Overall, a loss of power, especially with passenger, attributed to the problems mentioned above
- Turn signals not engaging properly. Oddly enough, the left signal comes on right away, but the right signal needs the left signal to engage before coming on
- Cosmetics: bump in the tank, paint scheme, foam on handlebars lacking, engine paint, etc.
- Electrics check-up

Maybe Robert can create a forum for how to's, and we could make threads based on the parts diagrams from Yamaha?

 

I started with the tear-down of the bike yesterday, and got off most of the rear + tank + mirrors.
I'm really disappointed with the "original" mirrors. They don't provide as big FOV that the universal mirrors did when they came with the bike.
I noticed the air filter can be discarded, as it was full of dust and the occasional spider. I'll be going for one that can be cleaned for the re-build.

 

Re: New guy in town

The front of the seat wore a spot on the tank through the paint and polished the steel. I for one like it that way.
There is plenty of space between the airbox inlet and the seatpan for it to gulp all it likes.

 

Re: New guy in town

Thanks. After posting, I did trick out the edge of the seat with rubber foam window padding. If not vital to airflow, at least it protects the paint on other components...

 

Hockey, almost everything is off the frame now. Only the engine, forks + front wheel, and engine remains.

I've seen the engine tool TimeToRide made, and began to wonder where to fasten the jig...

Once the mysteries of the engine begin to unfold, I suppose I need to take some pictures

 

This would be highly unadviseable. There should be no reason to remove the airbox once you have the engine rebuilt, and reinstalled. You will find that it will be a major task to get that airbox to seal properly again if you do cut it in two.

If you need to remove the airbox for any reason the general procedure is to remove the carbs, and exhust. Then unbolt the front engine mounts to allow the engine to pivot forward giving clearance to remove the airbox in one piece.

If you are trying to make removing, and installing the carbs easier. Just unbolt the airbox, and slide it back. This will give you approximately 1/4 - 1/2 inch more clearance on the carbs.

For air filter replacement. There is a removable panel on top of the airbox under the seat that allows access to the filter.

Ghost

 

@ Ghost:
Thanks for the info. I've tried to remove the airbox with the procedure you described, but there's simply not enough clearance.
The idea is to cut the airbox exactly where the air filter element attaches and mount a thin metal bracket around the airbox, sealing it with black RTV.


By the way, I had a nightmare tonight - after the rebuild, my Secaha would run absolutely silent. As if it were an electric bike. Imagine the horror....

 

might want to look at hogfiddles post here http://xjbikes.com/Forums/viewtopic/t=3 ... art=0.html before you cut the airbox.

 

Thanks Mav.. We got it out yesterday by tilting the engine forward. The engine is also out...

The airbox will still be cut, though

I also discovered that there are air valves on the forks... How does that NOT complicate dismantling them?!?

Also, how do I replace the existing ball bearing with a tapered type?

 

If its the same as the 81 seca the air valves aren't complicated at all. They aren't directly ported into the fork tube and just slide off while you are taking the forks apart.

pretty sure the tapered bearings are a drop in replacement. I know a lot of guys get kits from all balls

 

Thanks mav,

I noticed the arrangement of the air valves as I took them apart...

The rear swingarm was cleaned for paint and surface rust. After reading a post about rust near the sidestand, I started inspecting the frame.
My find was substantial. A HUGE crack on the underside, where the frame bends 110 degrees from the sidestand to the swingarm pivot point.
What would be the best way to fix this? I was thinking of cutting the area to a C-shape, putting a steel tube in, and welding on both sides... But I'm more than open for more or less creative suggestions.

 

Finall got to hand the frame and collector box for welding before the weekend, and a buddy has helped me dismantle the engine.
Head cover is off, and so are the camshafts. They both look ok, with minimal wear.

I also got to measure valve clearances:
Intake cylinder #1: <0,1mm
Intake cylinder #2: <0,1mm
Intake cylinder #3: 0,1-0,15mm
Intake cylinder #4: <0,1mm
Exhaust cylinder #1: 0,15-0,20mm
Exhaust cylinder #2: 0,15-0,20mm
Exhaust cylinder #3: 0,15-0,20mm
Exhaust cylinder #4: <0,15mm

Shim readings:
Intake cylinder #1: 295
Intake cylinder #2: 290
Intake cylinder #3: 290
Intake cylinder #4: 285
Exhaust cylinder #1: 265
Exhaust cylinder #2: 265
Exhaust cylinder #3: 265
Exhaust cylinder #4: 270

Any recommendations of change for one too lazy to look it up?

 

I've been keeping up the process, and we're down to the engine block now. Pistons are out and polished. I even managed to crack one of the pistons while polishing... Ebay, here I come. Not to mention that the wife struck back at me for possible heavyhandedness by cutting the tip of my finger with her piston rings...
Engine parts are being blasted with a lesser abrasive form of sand, and the engine internals will be sodablasted once that gets in house.
Using the shim calculation sheet from Haynes, I need 3 new shims for the intake, and 1 for exhaust.

 

Update since last post:

Got around to blasting the crankshaft covers and started on the clutch cover. Remaining are the engine blocks themselves, as well as carbs.

Yesterday, I received the "new" pistons I ordered a week ago. Shame the choppers didn't mark which cylinder the pistons belong to, but I can't imagine that matters all too much as long as I use piston rings from the one I broke...

 

I've ordered parts for a DIY ultrasonic cleaner as described here:
http://deiwhy.blogspot.com/2008/12/diy-ultrasonic-cleaner.html

Only needed the transducers really, since I've got a soundcard, software, and amplifier lying around anyway.


I've gotten the clutch drum out, and cleaned it. After taking off the clutch friction plates and pressure plates (and verifying that they needed replacement), I see that the drum itself looks a bit banged up where the pressure plates meet. Just wanted to check in with you guys to see if that's normal?

 

Update:
The ultrasonic cleaner idea did not work, so I bowed to order a small cleaner from HK for 35 bucks. We'll see how it works in a few days, I guess.
One thing that did work, though, is the soda blasting cabinet I made. It's got an air proof lid, fan that sucks the air out, and a bucket to collect blasted media. Pretty satisfied with that one.

 

Let's see the polished piston crowns, combustion chambers, and the blasting cabinet !!

 

Whoa yes, pics coming later today. I spend so much time with the bike to get it done for the season, that pics are considered second priority, hehehe

 

Takes a little more time to polish the pistons and combustion chambers. To be honest, I'm not sure if it's a good idea to polish those item when the polishing compound leaves residue - or did I miss something here?

Anyway, here is the blasing chamber. The rear sports a nice filtered fan to vent the dust out.

 

Finally done cleaning up the parts (only have the forks left), and it's time to start putting her together again.
Parts for the final drive and engine oil seals arrived last week, and they're all going in now.
Here's me posing in front of the shelves. The big shelf on the right are stage floorings that I've put together to serve their new found alternative purpose.



Aaaand here is the new seat cover. Some stretching was necessary, but I still didn't get rid of the crease in the front...



And here is the planned paintjob:

 

So, where are we at?

The following has been primed for painting:
- Centerstand
- Stock handlebars (considering a lower bar from Rizona)
- Carbs
- Front fender
- Passenger grab bar
- Passenger footrests

Paint will be bought inn later this week. I'm thinking Yamaha Black for the black parts - mainly because it will tone down the shine for parts that I wish to hide (like grab bar, footrests, brakes etc.) - and the original Brilliant Red for tank and stripes on the front fender.
Having a little trouble removing paint from the plastics using a grinder and fine sanding paper. It just eats through. Will need paint stripper for them.

 

Got to gun-painting some parts yesterday (grab bar, handlebars, rear foot peg brackets), as well as priming final drive, rear swing arm, and rear wheel hub parts.



But while I was putting the engine together for masking and prepping for priming, I managed to strip one of the upper case flange bolts (long, thin bolt)... It's located next to a similar bolt, just 2-3cm away.
I REALLY didn't need this right now...

 

During the weekend, I finished coating the rear footrests, rear swing arm, final drive, rear wheel cover, bars, and center stand.
The flash really does no justice to the nice semi-gloss coat. Thanks to the activator (or maybe the paint in itself), the surface feels resistant to road rash etc.





After prowling the forums today, I noticed that Darkfibre hung his engine using the front bolts. I have to admit this never crossed my mind
You can see a hint of the marks I managed to make while taking the engine case apart. This needs to be fixed. I don't believe the engine case is pressurized, but it's not acceptable to have these marks on the bike...

 

Picture of the freshly painted frame:



The wheels are painted and left for dry, and meanwhile I'm working on getting the engine in shape. The stripped bolt had - luckily - broken off without going all the way in, so it's possible to get out...

 

Got some new pictures of the process. Done painting all, except for the tank, which will now have be Yamaha Lava Red. Pretty close to the Brilliant Red - which apparantly no company can make in Norway...

I have to admit, the black paint really makes the brake lights more striking:


Valve cover painted and demasked:


New primary chain and guide in, connecting rods connected. Seems rods 2-3 are tighter than 1-4... Anyone with similar observations?


Some of the rest, ready to put in:

 

looking good - hope you keep posting till the bike is done.