6grand to go 70mph????

ok i am back this time my bike is pulling 6000 rpms to go 70miles per hour any adveise?

 

Sounds about right for a MAxim. I'm at around 5500 at 70mph but I rarely go that fast, mostly I'm on back roads. The Seca has an extra gear so it should turn less at 70

 

If you're turning 5500 at 70 and he has an extra gear he should not be pulling 6K. I didn't know the big Secas had the extra gear, I can only speak to 550's. On a 550, 6K is a little over 70 in 6th. But that's a chain drive 550. Slipping clutch? 750 Seca owners?

 

My 650 Maxim turned 6K at 70mph.

 

Check your speedo against a GPS or a nicer car. They have been off by 10% + or - .
All shaft drive XJ ' s have 5 gears (right?)
You'll need to go to a shop to check your tach for it's accuracy (unless you own a lawn service, then you can use a Tiny-Tach off a big mower).

A slipping clutch is very noticable.

 

81 & 82 Seca 750's have 5 gears

 

With the Maxim rear wheel, my Seca goes just above 70mph at 6K (5th gear). With the original Seca wheel, it would get closer to 75-76mph.

 

just thoght it was odd pulling that high to go highway speeds

ps i have no speedo cable i was riding with friends

 

dont worry, it will do 6k ALL DAY LONG!!!

 

True. Just getting into the "fun" zone.

 

My Honda VF750F was pulling 5500RPM doing 100Kph (60MPH) all I did was get a smaller sprocket for the rear wheel - only small by 2 (two) teeth and it dropped 500RPM.

 

Actually, It'll run 7K or even 8K all day. I ride my 550 in rush-hour traffic at 80-85mph for an hour+ commute and it just loves it. These motors are happier at 7K than at 5K.

 

i had ripped off my seca only has 5 gears lol god if it only was a 6 speed...and chain drive........and rear disk.........and oh who am i kidding i dont need that crap

 

6-speed, chain drive, pulls like a banshee right PAST redline if you'd let it in all 6... sounds like an XJ550. Two out of three ain't bad (rear disk unnecessary the bike is so light.) Sounds to me like you need a 550 too.

 

I was thinking the same thing.
:lol:

 

The chain over shaft efficiency advantage and the 6 speed gearbox make the 550 as "real-world" fast as its big brothers. With the grab strap removed, there is plenty of room (on the Seca anyway) for even someone over 6' like myself to be comfortable even on longer rides. Back in the day, I wanted a 650 Seca so bad I could taste it but could only afford the SR500. Fast forward 28 years, now that I have ridden both the 550 Seca and the 650 Seca... well, I bought a second 550. To paraphrase Bill Elliot, "these things rip!" 'nuff said. I think every 650 or 750 XJ owner needs a 550 for his second bike. There are a few of my fellow lunatics here that will agree with that.

 

I've been wanting a 550 for awhile now. Maybe after I work on the '82 for a bit I'll find someone who'll trade.

 

I also do 6 grand at 70mph on my XJ650 Maxim. It's just the way they're geared. Don't worry about it. These engines can run all day at 7 grand without an issue.

 

Standard Yama crap.. Highish revs in 5th at keep up with the traffic speeds on the hiway..but not enough power to hold that speed in 6th.
Typical for a LOT of yama models.

 

Strange... I also have an '82 SECA 750, but mine turns just about 5K at 70mph.

I don't know how accurate my speedo is, but I do know that the tach is quite accurate from comparing it to the internal RPM from the ECU.

 

My Mixim does 80 mph at 6k with my Seca rear wheel. What do you think about that. Learned to do that on this site. With the new cluch($80.00) it does about 85 mph at 6k. In about 500 feet. And I don't even ride it hard.

 

Geee.. You must own "superBike?? Or your Speedo is Fubar.
My Yama Racer 2 stroke with 70 Wheel Hp and a 240 lb weight can't do better.

 

Horse feathers! When I'm running along at 80 and need to zip past a truck or lay a little zoom-zoom on a cage, I generally just roll it on in 6th. RARELY downshift on the freeway (unless it gets slowed way down.) The 550 has sufficient cajones. Passing a car doing 60 on a two-lane blacktop is different (although it really just depends on how fast you want to disappear in the distance.)

Most people simply aren't used to high-revving engines at first and it does take some getting used to. But once you realize that cruising at 8K is NOT pushing the motor at all, it's a wonderful thing.

 

Runs at 8K all day guys? Even Yamaha says that they are not designed for sustained use over 7k. My Max cranks 6k at 70mph too and even with ear plugs, at 80mph and 7k I feel like I am abusing the old girl. Even so, those through the gears runs to 9500 sound SWEET!

Some of the 55+ bike crowd here in the Great White North have been talking about a cross Canada-US tour this summer and word of +100mph runs through Nevada crop up. If I go, seems the old Yammie won't have the kind of guts needed to keep up. So, are we talking trading or buying up to an XJ900? Most of these grumpy old men have hogs or beemers and to be out shined by a hog ain't in my nature.

Any thoughts appreciated.

 

look at the tach . most are redline about 10K

My 82 maxim 40 cruises @ 5400rpm/60mph ( thats 5 gears. wish I had 6)
I am convinced these motors love High rpms as long as you are not sustaining them for long periods.

 

here's how I get on the highway (most of the time):

1st, 2nd, 3rd, 4th.. shift at 9500 RPM
5th... I ease out of it so the old lady in the Buick can get the hell out of my way... then it's 9000 RPM in 5th gear, and whatever I have to do in 6th to keep up... :mrgreen:

Both of my XJs love the high RPMs. They're addicts, but who am I to judge?

 

OK, just to clarify:
Can I sustain 70~75 mph for 2~3 hours? 80? 90?
I'm asking because I once got carried away in my little Peugeot Vivacity scooter, and did 60 mph for almost an hour. Result: The 100cc, 2 stroke little engine overheated. Had to change piston, piston rings, sleeve, etc. :cry:
I don't want the same to happen to my '81 750 Seca.
Saludos desde Reynosa, Tamaulipas, Mexico!
macnifico

 

Ditto! (except I usually "short-shift" first-second at about 8K)

I regularly run my 550 at 70-85mph for an hour and a half; then turn around later in the day and do it again. (It's called freeway commuting.) The XJ never cracks a sweat. Once off the freeway and immediately into 20mph stop-and-go traffic, there is never any sign that the freeway romp had any adverse effect.

You should be able to run your 750 at 70-80mph all day.

Yamaha didn't design these bikes for the home market, they knew they would be selling them in the USA, with our freeways, and in Europe with the Autobahn. They were designed to sustain 70-80mph without damage.

 

Well, thank you for the clarification.
Saludos desde Reynosa, Tamaulipas, Mexico!
macnifico

 

So......how much to turn 100 mph? My bike only has the Reganometer and I sheared the speedo cable again! today anyway.

I hit 7100 RPM's in 5th. How fast is that? The bike is a stock '82 Seca.

 

I believe that is a Carternometer.

 

I did some research, I've been dissing the wrong dead President.

Carl is close, it's actually a Nixon-Ford-Carterometer. The stupid 55mph debacle began under Nixon; continued with gusto under Ford (where the speedo reg was BORN) but by the time NHTSA and the Commerce dept issued the new "speedometer accuracy" regulations (the 85mph speedo was buried in the new accuracy standards) it was on Carter's watch. Reagan actually saw the downfall of the 55 limit and was in office when the speedo reg got dropped.

I don't care no mo! I gots a 150mph speedo now!

 

This gives me a thought.

The DeLorean was also built during this era and comes with the 85 mph speedo. Anyone here who has watched "Back to the Future" will no doubt cry BS because the movie shows the car with a 95 mph speedo so that you can watch Marty hit 88 mph and travel back in time.

DeLorean Motor Company (not related to the original DMC Ltd) has made aftermarket speedos that go to 140 mph by recalibrating NOS 85 mph speedos.

Couldn't we get someone to do the same and have new face decals made for our Seca 750 speedos?

 

Recalibrating the Yamaha mechanical speedos isn't really practical. If you compare an 85mph, 120mph and 150mph side-by-side-by side, you can see that the difference is the ANGLE and DEPTH the magnetic spinning head "engages" the cup that moves the needle. You'd have to use parts from the different unit, so you might as well use the different unit.

The Yamaha mechanical speedometers all have enough of a similarity so that with some re-engineering, it can be done. Granted, it's easier with some bikes where the cluster just comes apart than with bikes with "canned" instruments, but it can be done. The "guts" are pretty much the same.

Easier to scrounge up a close or compatible NON-85mph unit from a slightly earlier or later bike. They're not hard to find, just gotta think outside the box a bit.