My 247C has quite a few false neutrals.

Yesterday at tthe trial the old boys running newer stuff, were fondly remembering that even when new, these Montys's came with some free neutrals kindly donated by Montesa.

Is there a fix, or a case of "they all do that sir"

Bless the old girl, she really shone on the loose, sandy hill climbs, such a soft 'n friendly engine but grunty when needed, love this bike.

 

yeah I know, no 6th!

Edited July 3, 20179 yr by iconic558

Mine seems fine, but I know people went on about Montesa gearboxes back in the day. At least you won't be unloading at 140mph like Guy Martin, though it may feel like it if it drops into neutral on a steep downhill. Those brakes won't save you.

Glad to hear you're enjoying it.

Edited July 3, 20179 yr by cleanorbust

Yep you do learn to double check before launching up a steep bank ...  some oils appear to make it better or worse.  Mine mainly jumps out of first and occasionally when  going into second.  No issue with the other gears.

I never owned a 247 but did help a couple of others sort gear problems on theirs.

I can't remember exactly but parts of the selector in the primary case are pressed together and come loose resulting in a less positive move of the selector forks. TIG welding the selector parts improves this.

The gear dogs and holes into which they engage could do with a bit more undercut. The dogs can be done with a diamond file or wet n dry paper on a stick. If the dogs are already rounded off as a result of sliding out of gear they may need a bit of metal adding by tig welding. 

The holes into which the dogs engage can be undercut with a dremel and drum grinding stone or a bit of dowel in a drill and coarse grinding paste.

You also need to check the gear selector forks are not bent or too loose and move the gers fully into position. you can check this movement with the gearbox built up in 1/2 the crankcase. Thinner synthetic gear oil will give better changes and less neutrals than the originally recommended EP90.

4 hours ago, dadof2 said:

Thinner synthetic gear oil will give better changes and less neutrals than the originally recommended EP90.

That is not my experience - when I went to lighter oil the gears were terrible - it was several years ago and I can't remember the exact issue but I didn't stay with the lighter oil as the bike was barely rideable.

thanks guys

I had the same problem with my 348 back in the day. I rearranged the spacers on the gear shafts and the problem went away.

17 hours ago, keychange said:

That is not my experience - when I went to lighter oil the gears were terrible - it was several years ago and I can't remember the exact issue but I didn't stay with the lighter oil as the bike was barely rideable.

The suggestion I made was a generalisation for bikes of the 1970s where a thickish oil like EP90 or 20W-50 was originally specified. On a gasgas pro or a Sherco switching from thin ATF to thicker light gear oil or 10W-40 generally improves the gearchange.

Just out of curiosity what bike are you referring to and from which oil to which oil did you try with unsatisfactory results?

dadof2 - as I said it was several years ago - I have a 76 Cota 247  I am pretty sure it was ATF  -  I currently use Castrol EPX 80W90 and apart from jumping out of first it is otherwise excellent