Manky Monkey Motors

Technical Section => Bike Tech => Topic started by: minimutly on August 18, 2019, 06:49:45 PM



Title: Xj650 midnight maxim rebuild
Post by: minimutly on August 18, 2019, 06:49:45 PM
Thought I might start a thread, even if the job is mostly done.
I bought this from a chap down Basingstoke way - he'd started  chopping it, cut off the back of the frame etc. Then lost interest, sold the carbs, footrests, headlamp, seat, sidepanels, rear mudguard, hamdlebars and controls.
I bought it for £110, with the intention of making it into a trike. But damn it all, I liked the look of what was left! So I spent a while collecting bits, including another XJ - this time a Seca. So that donated its bars and  controls, but that was it. So once I'd found some carbs - had to go for a set of Mikunis  from a 600, couldn't find any Hitachis, the engine fired up and ran sweet. Add all the other bits, including a seca rear wheel, and we have a nice bike(I think). One thing to note about the Mikunis, they are larger at the butterfly end, both inside and outside, so I had to machine the bodies down to fit the rubber inlet tubes
Currently the rear suspension is hagons (ebay), I made a tool to strip the springs off to test the shocks, really useful tool. I have ridden it, it rides beautifully for a 1980s bike.
Best of all, it probably hasn't cost me a fortune - I expect around £350 all in.
Looking forward to getting it on the road. Oh and, last weel I fired up the Seca that came on its side on a pallet - once the smoke cleared it was great.


Title: Re: Xj650 midnight maxim rebuild
Post by: Manky Monkey on August 18, 2019, 09:57:19 PM
Photos as requested Sir.
Sorry, but the Seca shot's a different format, PNG, not JPEG), & the forum won't accept it.


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on August 18, 2019, 11:02:08 PM
Thanks Andy, I'll see if I can save the seca pics as something else. Oh and send a pic or two of the trike and the maxim as it is now.
Huw


Title: Re: Xj650 midnight maxim rebuild
Post by: stinkey on August 19, 2019, 06:11:45 AM
Well at last something to look at  ;D


Title: Re: Xj650 midnight maxim rebuild
Post by: hydro on August 20, 2019, 10:57:11 PM
Windows "Paint" can open PNG's then you can click File, Save As then select JPEG


Title: Re: Xj650 midnight maxim rebuild
Post by: Manky Monkey on August 22, 2019, 09:40:43 AM
Give that a go Huw, then send 'em to me again :)


Title: Re: Xj650 midnight maxim rebuild
Post by: Sid_Vicious on August 22, 2019, 04:19:01 PM
The tool you made sounds interesting. So if you would be so kind to take a couple of pics of it and maybe a few messurments it would very helpful. The build sounds like you will have a nice bike when you finish it.


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on September 01, 2019, 10:53:55 AM
Morning monkeys.
I've sent a pic of the de-springer tool to Andy so hopefully he can resize and post for me.
Dimensions wise it's inch box, needs to be a bit longer than your longest shock. The tricky bit is making the spring locating bit - firstly it has to lock - you could do this by drilling and having a pin on a chain, but I just allowed enough rocking movement for it to lock as it was tensioned, and yes since I'm a lazy booga and didn't paint it the lock works fine. The other difficult bit was shaping it to suit the spring winding and diameter, took ages. Ideally I'd like to coat that bit in some kind of plastic/rubber stuff to prevent marking the springs, but with care I haven't found a problem yet.
Lastly it doesn't have a mount - it's designed to fit in the vice.


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on September 01, 2019, 12:00:18 PM
Here we have it, courtesy of his mankyness


Title: Re: Xj650 midnight maxim rebuild
Post by: Manky Monkey on September 01, 2019, 02:39:39 PM
:)


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on September 01, 2019, 10:48:27 PM
Andy missed this pic - can't get the staff these days.
Thanks mate
I dunno why I put the set in the lever that way - perhaps I made a mistake...
On another note, took the black maxim out for a spin today after rerouting the throttle and clutch cables.
It goes Ok, revs a bit in top gear, I was looking for 6th more than once. Rides and handles beautifully (I am comparing it with a trike, and a hard tail at that).
Still some work to finish, seat mounts, indicators, rear tail thingy and lights.


Title: Re: Xj650 midnight maxim rebuild
Post by: Sid_Vicious on September 02, 2019, 04:02:05 PM
Thank You Sir. Since I am norwegian and have to translate everything inside my head to understand the description of things it is very helpful with a picture. The tool looks great and I will probably copy some of your design when I am gonna refurbish some of my shocks.


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on September 02, 2019, 07:19:03 PM
It's a mark1, but works well - spring off in 20 seconds or less. Better than ratchet strap roulette


Title: Re: Xj650 midnight maxim rebuild
Post by: stinkey on September 02, 2019, 08:47:19 PM
I was confused because you said  a despringer tool?  And I was thinking no way will that work on my front end?


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on September 02, 2019, 10:38:11 PM
Maybe I should have taken a pic with a rear shock in there  ;)


Title: Re: Xj650 midnight maxim rebuild
Post by: stinkey on September 06, 2019, 06:30:03 AM
Yes..us blind older gentlemen need all the help we can get ;D


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on November 27, 2019, 04:42:43 PM
Quick update on this - related but not actually anything to do with the xj - I passed my theory test today  :D
Cbt done a while ago. So mod 1 here we come. Can't wait.


Title: Re: Xj650 midnight maxim rebuild
Post by: Manky Monkey on November 27, 2019, 07:51:42 PM
Woo hoo! Well done mate :)


Title: Re: Xj650 midnight maxim rebuild
Post by: BikerGran on November 28, 2019, 08:55:52 PM
Excellent!


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on May 20, 2020, 11:53:24 PM
Failed it, 3 months ago now must be....
Anyway, been working on the 650 on and off. Bought a 600 airbox, cos I didn't want to spend a fortune on K&Ns, and the 600 airbox fits my 600 carbs and is bigger and neater than the 650 one. Oh and it goes on without removing the engine !
Plus point is that the sidepanels I was making from ally look like they will fit, as long as I take the helmholtz resonator off the side cover, whatever the advantage I will have to live without it. Really looking forward to passing my test and riding this - I allready took it for a spin - it runs like clockwork, smooth as you like. Not bad for a nearly 40 yr old bike.


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on June 14, 2020, 12:47:00 AM
Had to cut the airbox mounting crossmember out to make and fit a mount for the 600 'box. Also cut out the rhs sidepanel lugs, so I could fit the new rubber bobbins I made. Now all I need to do is make the mounting tabs for it.
Might try a filler rod made from original sheet this time.


Title: Re: Xj650 midnight maxim rebuild
Post by: minimutly on June 14, 2020, 11:19:56 PM
Pic of one side, I rebuilt the carbs, boots and airbox today after making the bracket for it. Thanks andy for resizing it for me.