Speedometer Problems - XJ750 Maxim

Greetings!

I just purchased an 83 XJ750 Maxim from a friend. It's a beautiful bike with only a few cosmetic issues and no major mechanical issues.

The only thing keeping me from riding it, is that the speedometer doesn't work properly. It goes up to 20mph, then just stops there. No matter how fast you go, it tops out at 20mph.

The instrument cluster is all off the bike right now, so I'm hoping someone here can tell me a fix, or at least 1 or 2 things to look for before I give up and take it to a shop (I really don't want to).

Thanks!
-Robut

 

Check the speedometer unit on the front wheel. You will have to remove the wheel from the bike. There are tabs on the wheel side that fit into slots on the speedo unit side. If they weren't aligned and got tightened down the tabs can get bent down and not turn the speedo unit. That's what happened to mine

 

check the internal cable see if it is broken

 

also check this thread out
Seized Speedometer Drive Unit

 

Thank you for the replies! I will check both suggestions as soon as I'm done with dinner! My old xj650 was a lot of fun so I'm eager to get this new one on the road.

 

OK, I took the wheel off and the Speedo Drive Unit SEEMS to be functioning properly. It spins the Speedo cable when I rotate it with my fingers. Also the tabs that seat into the Speedo drive unit seem to be fine. The tabs fit snugly when I put it back together. Also I forgot to mention that the previous owner (a trustworthy friend) said he already tried 2 brand new speedo cables and that didn't fix the problem.

Unfortunately, I didn't read the thread you linked, @XJ550H , Until I had already put the wheel back on. I never thought about using an electric drill to test the speedometer in the cluster. That's the next thing I'll test, though it'll have to wait for tomorrow at this point.

 

Welcome to the Club. What's going on with the solenoid sticking out there like that?

Gary H.

 

Be careful using a drill. I did that to mine and accidentally had the drill turning the wrong way and it broke the pointer in half

 

Gary, The battery is out of it in the picture lol

Yardawg, thanks for the heads up!!

 

Yes it is. Lol.

Gary H.

 

Oh! I see what you're saying, Gary. It's because I had the battery from another bike hooked up and sitting on a bucket next to the bike. Just haven't bothered to put everything back in place yet

 

Now it makes sense.

Gary H.

 

Hey Robut, welcome. I was planning to give you this thread to help: http://www.xjbikes.com/forums/threads/speedo-and-tach-dissection-with-pics.15303. It explains lubing and bringing one back from near dead.

But then I read your last explanation about the PO trying 2 speedos already. Sounds like it might be a speedo hub issue on the front wheel?

 

Well he tried 2 speedo cables but not brand new speedometers. I will definitely check out that thread. Thank you!

 

Thank you for that link, ColoradoDan! It is very informative. Seems like that may be my issue. I have ruled out the speedo hub, the meter clutch, and the cable, so I'm going to try lubing everything in the gauge cluster to see if that helps.

Narrowing it down!

 

this link may help with basics of Removal and disassembly


Breakdown of the 750J Gauge Cluster

 

Perfect. Thank you!

 

Glad it helped. I just repaired my speedo this month with some parts from another forum member, and that was the how-to link that got me there and back.