Yamaha Seca 650 Turbo thread!

I have owned three of these and said I wouldn't buy another after the first one because it was dated and I had to have the newest and fastest. That was when I was real young and real dumb. Well when I was stationed in Maine I bought another one. Fixed it up nicely, then I bought another one while stationed in New Mexico. A lot of what I know and have done was due to trial and error initially, but I have found some great info on this site: www.turbomotorcycles.org

Here is my .02 cents:

They are great for touring at or above the speed limit. The ride is nice and they handle okay stock. They don't brake for $h!T though! If you are going to keep this bike, may I suggest some things to make her a keeper?

These things I suggest are only after you get her tuned up and running right under boost. That means, carbs cleaned/rebuilt, plugs, upgrade to better coils and wires too. If she is not running right under boost after all of this, go to step 4. Ah do step 4 anyway while she's apart.

1) Swap the entire front for a later model Yamaha or Suzuki. The forks on these bikes are spaghetti noodles and the brakes are the size of DVDs. I opted for a late model FJ1200 front end on my 2nd Seca Turbo. It offers better handle bar position and it has 41mm tubes with better damping, better brakes if it is after 1986 and it is a near drop in because the steering head pin is the same, just the bearing cups are different. Check out www.ohiocaferacers.com for stem/bearing sizes then go to www.goallballs.com for steering head bearings and look under details and you will see what bikes your bearings fit. The ohio cafe racers site has the best swap info I have found to date. I found this info on www.xjbikes.com

I liked the FJ1200 swap because of the updated speedo and tach, plus the other gauges that come with it or you can just reuse yours. I also like the fact that it's a Yamaha piece. I almost went Suzuki Katana 1200 front though. they seem to be a nice fit also. If a whole front end swap is not in the cards, I do agree with the previous posters that Galfer steel braided brake lines are a big help, but I would suggest using 1985/86 MAxim X dual piston calipers and some performance brake pads. The Maxim X calipers bolt directly to our forks. On the 2nd Seca, the FJ1200 front wheel was a 17" tri spoke unit that was an exact match to the Seca 900 18" rear wheel with disc brakes that I had from a donor bike. If you can find a donor 900 (good luck) grab the rear wheel and brake assembly. The rear swingarm won't work unless you do some grinding on it and it will only allow a 130 size tire to fit it. If you look at our Seca and then look at other Secas you will see ours is indented on the drive axle side. (All three of mine have had this anyway) I have a 140 series on mine. With a cut out of the drive shaft area and move the spacer washer from the right side under the drive assembly, I will have room for a 150, maybe? Oh yeah the 1st and 3rd Secas have the 18" Vision front wheel on them. The Turbo and Vision wheels are identical, the Turbo ran a 19 and the Vision an 18", both are only 2.15" wide though, where the Seca 900 and Fj11/1200 wheels are 2.75" allowing for more tire contact patch.

2) I added longer shocks to the back of mine of the one I ride now. The stockers are 12.5 eye to eye. I added 14" shocks off of a Honda ????? I think? The 14" shocks are too high. Handles great with the added rake and will carry a nice big load and not bottom. 13-13.5" should be about perfect. I am looking into adding a Virago mono shock to my latest Turbo.

3.) The bottom end is lazy on these bikes, mainly due to the restrictive air filter box that filters air for the reed valves in the surge box and the turbo inlet. I took my box off and added a cone filter to the surge box inlet on the back side and one directly to the turbo inlet. Boost picked up much quicker and felt more torque earlier. You could and this is just throwing it out there as I have not done this yet! You could remove the reed valve/surge valve plate and add a custom reed valve setup. Will breath better on the bottom, but you will lose the safety of the blow off valve. It opens at 15psi to prevent over boost. Running a good boost gauge and boost controller is in your best interest at this point. The stock gauge doesn't tell you what psi you are at, just whether you are boosting or not.

4) If your bike is running good but falls on its face under boost, get rid of the old gas cap. get a new automotive type and drill a hole in it so it can breath. Also add an automotive type fuel filter, not a gigantic one, but one that has 3/8 in/out and one you can see through. Believe me this is two of the easiest mods/fixes to a myriad of fuel gremlins you may encounter. If the gas cap trick doesn't work, check your fuel pressure regulator and see if it is rising 1 psi per 1 lb of boost pressure. There are a couple of auto types with adapters that you can adjust fuel press to your liking, especially if you are raising the boost up. If the gas cap, fuel filter and pressure regulator are all operating right, then the last culprit would be low pump output. Remember the pump is 28 yrs old, it should be putting out at least 25psi at idle. If not get another one. By the way the part number is no longer carried so with some ingenuity and it being all I had anyway I ran a Bosch inline from a Ford truck. You can find them in good working order on most any Ford truck on the frame rail or a Volvo just forward of the gas tank in the filter housing. It is a bit bigger than the stock unit but works flawlessly under boost. They flow 155lph @ 45psi at idle on a stock Ford fpr (28psi on the Seca FPR) and can handle up to 95psi. These Bosch units are good for 500 hp when two are plumbed in series on a fuel injected turbo 2.3 running 22psi of boost. So they will be more than capable of handling fueling for the Seca turbo.

There are other things you can do to bring out even more performance in these bikes. If interested in some of what I have planned for my latest Seca Turbo or you have some ideas swimming around, please hit me up and let me know. This is a forgotten sport bike and there are ways to make her more of a desirable sport tourer than she already is. Donor bikes are getting cheaper, ideas are getting better and these bikes are waiting for some attention.

My dad and his brother both had one, my dads was grey and my uncles was yellow.

My dad still has both bikes. Story goes my uncle wrecked his, borrowed my dads and then wrecked that one too, so now my old man owns both.

This was the first street bike i rode for my first solo ride with my dad one sunday morning when i was 15. I didnt get my motorcycle license until i was 17. Im pretty sure i dropped it that day too.

Pretty sure it has 100,000+ miles on it.

Great thread, thanks for bringing back a great memory!

Although I like bikes in this category for nostalgia if anything else, I'm not sure why you want to get it for 'longer distance touring,' ...especially 2-up, as it is REALLY NOT suited for that. I suppose you are using that angle to get approval from your wife...whatever works for you.

Doesn't look like they did, no. Even with the small amount of pressure from the turbo, oil doesn't like running uphill.

The Seca turbo bikes are fit with a special oil scavenging port in the oil pump to pull the oil from the turbo. My check valve was stuck open on mine so I ran a wildwood one-way check valve.

The bike as whole does great for two up touring. The first SECA was ridden all over the Carolinas and into GA several times with a passenger and no complaints about ride quality. While stationed in Maine the second Seca was blasted up and down northern I95 that leads up to Canada and south to Boston, with plenty of trips to Lake Winnipesaukee, NH, again loaded with passenger and saddlebags. The wife and I rode my last one down from Ft Collins, CO (just north east of Denver) to Albuquerque, NM where I was stationed. The ride is nice and the bike does very well with two up because the seat is long and wide for comfortable touring with a passenger. The shocks are a hurdle getting adjusted for optimum ride quality with a load, but they do their job once adjusted to your liking. The fairing does an excellent job of dispersing the wind up and around you and your passenger. The fairing compartments are a huge help with storage and you also have enough dash and fairing to install a radio with little mods. The '82 tank is 1 gallon smaller than the '83, so an '83 tank is a desirable upgrade for long haul touring, unless you like stopping for gas more often. It's also, "Run what you brung" thing. If this is what he wants and can afford, by all means go for it. Again, I've had three and each one has been a reliable steed in every respect. I know we'll hear, "Buy a bike more suited.", well this one is with little work. What long haul tourer on here is good to go right out of the box? I bet there are mods and upgrades to every bike on here for one reason or another. Why not mod this one too?

I agree, the Red/White Turbo is a beauty!!!!! As I have owned both a GPZ turbo and the three Seca turbos, I found this article that some of the naysayers may be interested in reading. There was no way i would long haul the GPZ due to it's agressive stance, but these Secas are so user friendly. check this article out:

http://www.motorcycleclassics.com/Motorcyle-Reviews/July-August-2008/Turbo-Wars-Kawasaki-versus-Yamaha.aspx

All I have to say to the people that say they're ugly and slow and yada-yada-yada... You probably never owned one. There's nothing like a turbo kicking in at 6500rpm to wake you the hell up! Yeah, a heavy bike. Yeah, old tech, yeah carbs... But until you sit on it and see how damn comfortable it is, then I suggest you just don't comment on what you don't know.

I've raced mine beside modern 1000cc bikes like Ducati's and R1's on the backroads out here and kept up repsectfully on straights, and right on their heels in corners. Keep the turbo running coming out of the turns and you will leave them behind you. Many of my friends just look at me with disbelief after a day's riding. I look at them and say, 'Yeah, she's old, and she's STOCK too! What's YOUR excuse?!'

On one particular day I took a 30mph country backroad twisty at 80mph... with a passenger! It gripped and came out of the turn pullling the front tire off the ground about a foot till I let up. Slow? Since when is 135-140mph slow for a 650??? My 2003 FZ-1 would only do 150-155mph...

So chalk it up to superior aerodynamics of the Turbo for such a heavy bike to get up that fast. Honda's and Kaw's Turbo aerodynamics SUCKED. Like riding a naked street bike.

The only bike similar in the 'pull' respect is my 2006 Honda Interceptor when it also kicks in its four vavles at 6400rpm. I'd say it has about half the seat of the pants pull of the Yamaha turbo though.

I've owned two 1982's. Both pristine condition. I should have never sold my first one. It was the best one of the two. These bikes are all day comfy on the stock saddle. Great for touring. No, it's not a dual sport, but on the open road it's just a very competent bike. I got 55mpg on mine. That means well over 200 miles range per tank, even on the 1982 which had one less gallon capacity than the 1983, the later are hard to find these days.

Yeah, I loved that bike. I'd buy another just for the ear to ear shit eating grin it delivers.

By the way, for anyone that owns one, Dunlop makes the best replacement tires for that bike, and it's a matching set, not two different models front and rear.

I've noticed that everyone that repaints their Turbo always goes with whatever color scheme they like. While that red and white is nice, there's a reason he didn't repaint it stock. There's no release of that paint code! But a good paint shop can reproduce it pretty faithfully. I know. I had a few panels redone and you can't tell. People that rebuild them also gripe that they couldn't find the striping kit. They're available through aftermarlet, so that's no excuse.

Btw, in Europe they had this same bike as a 750 with fuel injection, sans (without) turbo.

I remember lusting after these bikes when they were new. I bought a new leftover 1981 Seca 750 in 1983 for about $2500 Cdn as my first bike and could have bought a 1981 Seca 900 or an XS1100 for $3000. They were still trying to get $5k for the turbo, though.

Within 2 years NOS Yamaha, Honda and Kawasaki turbos were going for $3k out the door and the power up kit was retrofitted to all the bikes in the showroom. By then, the interceptors were out (and the GSX-R's were coming) and all the turbo bikes were boat anchors on the showroom floor.

Thanks for keeping the memories alive, guys.

BTW, if you love old bikes, check out Mitch Boehm's new mag Motoretro. http://www.motoretroillustrated.com/ Mitch is a great writer and is working hard to keep the stories alive. No affiliation, just love the mag and old bikes.

In 1986 I bought an '82 Seca Turbo w/2400 mi.I test rode it and when the boost kicked in I knew I had to have it.I bought it for $1600.The dealership had one in the crate for $2200.In 1998 I sold it for $1000 w/62,000 mi on it.It cost me .01 a mile to own it.No major problems,it was hard on batteries. I think being enclosed behind the bodywork catching all the heat from the engine was the culprit.The cam chain was at the end of its adjustment and was getting a little noisy toward the end.
That was back when I was young,I couldn't do it now..............Jerry

Howdy y'all. Just picked up a beater '82 Turbo Seca done in a red color (stock?) and began tearing it down for a look. Last registered here in Ca. 2001, so it's been sitting over 10 years. Unfortunately, while unloading it I let it slip off the ramp and it went down on the right side although the back wheel was already on the pavement. Not too hard a fall but smashed the right front turn sig lens-- anybody got a spare?.Need a new windshield too!!!.. I noticed a lot of oil on the back side of the engine fins so it appears to be a leaker and not well cared for. Anyway, found a pristine looking 2nd turbo 650 motor in S.D. on ebay and bought it, so once I get that home I can dig into the top end and sides for inspection and make sure all is well before sticking it into the frame. I read a couple of good blogs here and I am thinking of swapping forks and brakes off another bike like others have done to increase braking and front shocking action. I heard the FZ600 forks will slide into the triple clamps and give better action overall, is this true?.. I have already upgraded a couple of pre-2008 KLR650s with both YZ450 forks and DRZ400 forks setups and these swaps made the KLRs awesome bikes to ride with REAL stopping power.....anyone know the best and easiest fork swaps for this 650 turbo Seca?? One blog said the FJ1200 triple clamp set will fit the steering head with minor mods?? Anyone done this yet?......I plan to sandblast this bike down to bare steel and build up as I have done on some others I have rebuilt, so a few improvements will be in the works as I plan to keep the bike over time...I had the 1st GSXR750 back in 85 or 86, a few '75 Norton 850 Commandos, BSAs, FJ1100, GPZs, KLX650s, KLR650s, and much more since I ain't no spring chicken! But I want to have fun rebuilding this unique little 650 turbo....any input will help....thanks!!

I wish I had experience with these bikes, but sadly don't. Like you, I've done multiple front end fork swaps. My latest is an Ohlins front end on a rebuilt XR600R that I'm making into a flat tracker. I've done XR650R forks on a Honda Transalp as well.

I hope you will keep us up to date with the NOW pics and the build as it progresses. Man, if I was you I'd go all out with the front in swap and do something like an R6 front end!

there is one for sale on ebay right now for $500.00
just search yamaha turbo. not mine!

This thread is great, my old boss who's a big bs'r would tell me about this turbo bike he used to have which i figured coming from him was typical bs but they actually do exist.

Reading thru here really has me wanting to ride one just for the experience, thou his words of knowledge are if it scares you twice get rid of it because the third will get you.

OK... Been tearing down this old bike and man it's going to be a ton of work..everything filthy, greasy, caked dirt, oil, and rust all over. Previous owners rode this bike into the ground until it just gave up the ghost I think..typical L.A. based idiots here--- no shortage of abusive dumbass riders around THIS city...I'll get the carbs off tomorrow and rip this baby down to the bone....really surprised by all the wiring and lines all over the place, -plus just the WEIGHT of this lead sled.....feel like cutting off the subframe and building one of aluminum or grafting on a section from another more modern bike. crap, they really believed in STEEL in the "old days"....(my era). I'll probably graft on an FJ1200 fork set with better brake system....probably do all the fairings in a darker gun-metal metallic silver-grey two tone with a lighter silver on the bottom section and use a white/red/black dividing line......I think that would give it a classy look, still very "80s"....I'll post pics tomorrow.

Send me your address via PM and I will send you a CD with all the manuals, plus adds, tips and tricks, and other information on your bike.

Jim

I restored mine last winter. It's my favorite bike of the stable. The front end has Progressive springs, new pads, and Speigler brake lines: works great. I shimmed the safety pop off valve with a washer and along with the cheapy ebay boost controller it is bumping 18 lbs of boost.

These bikes were ahead of their time with self canceling turn signals and lcd gauges.
It pegs out the factory boost gauge so i installed this:

Pic of the pop off valve and surge tank:

Here's a few pics of the bike when I got her home, stripped her naked, and looked at her in her sad, neglected state, like an old debutante seducer now aged and cast off into the "nursing home". Not real purty anymore, but I will do the necessary CPR on her, do some mechanical surgery, a few new parts, a bolus of epi, some sodium bicarb, 300 joules of defib with the paddles, and hopefully give her a shot at once again bringing a smile into a young man's heart...especially with that turbo kicking in at speed--- yeeeee-haaaw!!!.......and today really blew my mind as I tore off the valve cover and beheld what looked like a brand new top end without a speck of old oil, dirt, or even discoloration...man, you talk about not judging a book by the cover cliche......someone must have just rebuilt her top end before I got her. Looked like brand spankin new cams with a new timing sprocket and chain and valve shims smooth and untouched by a cam lobe.... I feel the urge to pull off the head to see if the cylinders and pistons are new.....this is getting interesting and intriguing...the guy I got the bike from said the previous owner was putting it out on the street 11 yrs ago as abandoned junk....he rolled it into his den and displayed it for 10 yrs....I wonder why-- just old technology at the time???....cant seem to load photos into this page.....