MZ/MuZ Riders

I have a 1998 Mastiff that I'm using for commuting and winter fun. The gearbox has been getting worse and worse over the last few months- it keeps falling out of gear so I've decided to swap the engine as it'll be cheaper than repairing the gearbox.
I've found a low miles 2006 XTZ660 engine, will this bolt straight in? I know the older XTZ 660 engine will, is there any difference between that and a later XTZ660 engine?
If anyone in the UK has a good XTZ engine I'll certainly take it off your hands!

It's probably just a selector gone in your gearbox and doesn't in any way warrant lobbing the motor to one side, although i understand your logic if your not mechanically minded. The XTZ 660 motors are all the same and will fit your bike,the XTX is the fuel injection version and isn't really worth entertaining. You can use XTZ 660 Super Tenere, Yammie XTZ660 i.e SZR 660 Super Single, MZ Skorp, Stiffy or Baggy motor, all the same.

We (Slipstream) have a fully loaded and ready to go tuned motor for £1500 if you want it. Worth a lot more than that and it's not been used since we rebuilt it. It's listed in the For Sale section. Otherwise check out some breakers yards, etc. Trouble is you want one with at least 3 month warranty or one that you can guarantee the mileage. If not your asking for trouble, out of one frying pan and into another so-to-speak!

Hope this helps...

Wonk is right. You don't throw out an engine just because a gear slips out.
Which gear slips out?
It can't possible be all of them. Probably the 5th and possibly the 2nd as well. They are the usual suspects. If you pick up a used XTZ engine, the 5th gear is probably worn almost to the point of slipping out as well. All the engines Wonky listed have the same transmission except for the SZR which has a longer 1st.

b

It's falling out of 2nd 3rd and 4th. Occasionally it'll fall out of 2nd and reselect 1st which is fun!
The trouble is I need the bike every day so I don't have the time to strip the gearbox and wait for gearbox parts to arrive. I did look into fixing it and it could easily cost £150 in parts before labour. I can get another engine for under £500 and swap it myself in a day which seems like the safest option.

I've been offered a 600 miler XTX engine, will this not fit? I didn't think the fueling method would affect the engine design. What's the problem with this one?

Wonkmeister - Much as I'd love a fully tuned motor I need to save my money to spend on my Guzzi's! I only paid £650 for the MZ a year ago so I need to keep the repair costs down.

Thanks for the help.

The XTX engine could be used but you need the wiring loom and CDI to match, these could cost you a small fortune if you don't buy the motor with these parts. TBH i would stick to your XTZ motor. Why not buy the parts you need for your motor and while it's apart have it freshened up? You could even have a bore and an oversized piston fitted while your at it if you wanted too! I wouldn't think it would cost more than £500 to have parts replaced , as i said, lobbing the motor out to one side seems a bit drastic to me, although i understand you need to use the bike. You can pick XTZ motors up for around £250 - £350, i wouldn't pay more than that, especially if it's not guaranteed! I'm sure i've got second-hand parts that are in good order that you can buy from me. I would seriously consider spending money on your motor rather than buy another, how many miles has the bike travelled? It could be just the selectors damaged and NOT the gears anyway which is even cheaper than replacing all the gears themselves....i'm sure Keith had the same sort of problem with his motor too!

The bike has done at least 45000 hard miles, it's generally pretty tired and I'm not capable of stripping a gearbox.
Point taken though on the electrics for the XTX motor.

Wonkmeister wrote:You can pick XTZ motors up for around £250 - £350, i wouldn't pay more than that, especially if it's not guaranteed! I'm sure i've got second-hand parts that are in good order that you can buy from me.

Do you have anything suitable? Much as I'd love to freshen the motor up I can't afford for it to be off the road for more than a weekend at this time of year and I need to sort it out very soon.

Gutsibike, Off the subject, but which Guzzi's do you have? I have a 2001 Jackal that I bought new a few years back and LOVE it. Good luck- Ed

I'll check with Martin and see if we have anything laying around, even a bottom end would suffice! Then all you'd have to do is swap the top-end over and have it timed up...leave it with me and i'll do some home-work.

gutsibikes - If you're near me (15 miles from Glasgow), I've got a 29,500 mile Skorpion that I'm going to break. The engine's still in the frame, so you could hear it running if you're interested.
I might be interested in the XTX 660 engine if the price is right. It should fit into a Skorpion frame OK, but does anyone know if the exhaust headers come out at the same angle, and if there's likely to be any other major problems fitting it. (I work in the electrical field, so making a wiring loom's no problem).
Norman
http://www.mzskorpion.net

Wiring is NOT the issue here and neither is the XTX motor. The XTX motor is basically almost identical to the XTZ motor, but fuel injection. You need the CDI and loom for the XTX motor because of the correct mapping and engine management for the fuel injection. I'm not questioning your ability as an electrician but it seems like a whole load of hassel for the sake of having the correct loom which is readily available, although you'll need pretty deep pockets for a new one. We are very close to finishing our first XTX motor tune, what we have done to this motor is very radical in terms of injection system and other mods and we had to buy an engine management system for it that cost £800. The wiring loom for the XTX isn't a couple of wires that locates round the bike, it's pretty hardcore for a single cylinder engine.

Be very wise when messing with this kind of stuff, you might be a great electrician but if you get it wrong, say bye bye to your motors "brain"...and maybe even the motor!Be safe, be smart, use OE, then mod...learn by the mistakes others make i say!

Good luck anyway!

I can offer you a complete XTZ cluster, mainshaft and layshaft with all gears in good condition for 150€ +postage. They came out of a Skorpion with only 20000km when a SZR cluster went in. If you are interested, write me off list.

Changing the cluster will only take may a 2 hours more the the engine swapping you are considering.

edec wrote:Gutsibike, Off the subject, but which Guzzi's do you have?

T4/LMIII bitsa, a Nuovo Falcone (now that's a real thumper!) and a Convert at the minute. I've had a V11, 1100 sport, G5, V65 Lario and quite a few others. I'm probably addicted to them.

Wonkmeister wrote:gutsibikes - If you're near me (15 miles from Glasgow), I've got a 29,500 mile Skorpion that I'm going to break. The engine's still in the frame, so you could hear it running if you're interested.
I might be interested in the XTX 660 engine if the price is right. It should fit into a Skorpion frame OK, but does anyone know if the exhaust headers come out at the same angle, and if there's likely to be any other major problems fitting it. (I work in the electrical field, so making a wiring loom's no problem).

The XTX is at http://www.cheshiremotorcyclesalvage.com, they want £499 for it delivered. I don't want the hassle with electrics as I need to sort it all in a weekend.
Can you PM me with a price for your Skorpion motor? I'm in Yorkshire but I could travel up hear it running and help you remove it all in one day. Is the gearing the same as the Mastiff gearing?

XTX is similar to the XTZ motor, but different enough that I wouldn't do it.
It's not that big a deal to fix the transmission.....I would fix it.
Gearing on the Skorp XTZ motor is the same as the Baghira XTZ motors.
I hope to go ~100000 miles before I rebuild the top end.

henri

Hi

Just pick up this thread as I don't come here to often anymore. The problem I had with my gearbox was a worn selector drum. The wear was in the track that operates the 5th gear selector fork and allowed the gear to slip out, occasionally slipping back into 4th.
As I already had another engine from a XTZ660 Yamaha siting in my garage, I just swapped them out.
I really must get around to rebuilding the old motor though as it is quite handy to have a spare around.
BTY this is the 2nd engine I have replaced. The first suffered from engine failure. When I took it apart I found the following
Big end failed
Oil pump shot, I think due to parts of the big end going thorough it
Piston and barrel with severe seizure markings, not sure if this happened at the same time though
Not to sure why the engine failed as I had always changed the oil regularly and didn't over rev of run the engine at low revs on high throttle openings either.
For reference the surfaces of the gears were unmarked after 35000 plus. On teh engien with the failed gearbox all gears are still ok as well.
I only use the Baggi for fun now as I retired it earlier this year and brought an Aprilia 660 Strada. Compared to the Baggi the engine is a lot revier than the old XTZ engine with what appears to be a little more top end power. It nowhere as sweet an engine at lower revs though. In common with the XT660X & R Yamaha's the bike suffers from surging between 3 and 4000 rpm. A lot of owners are using power commanders to get over this problem as neither Yamaha or Aprilia seem to be able to cure it with out the later electronics utilizing a Lambda Sensor.
Both bike as still nice to ride though. Completely different to each other and my 1500 Goldwing

Keith

Hmmm,
big end failure = over rev damage, oil starvation ?
Shift cam wear in 5th gear = a baffler , unless it was metallurgy failure.