Missing gears

rusty76

Joined Sep 2009

474 Posts | 1+

Leicester, UK

Discussion Starter
• Mar 9, 2011

• #1

It's not unusual for me to miss gears and find false neutrals but yesterday at Donnington it happed quite a lot (both up and down changes) sometimes with some fairly scary results. Anyone got any ideas what the cause(s) might be? I've changed the clutch lever recently but can't think of anything else

 

england 2

Joined Jul 2008

2K Posts | 4+

U.K.

• Mar 9, 2011

• #2

Ensure you push pull the lever as far as possible , do`t be too nimble with the change

 

Nobist

Joined Jul 2009

2K Posts | 0+

Sunny Astley GUNCHESTER Ingerland

• Mar 9, 2011

• #3

I bleed the brake/clutch levers everytime I change them now after getting stranded a while ago after swapping levers. Doesn't do any harm any roads for new fluid eh.

 

grin factor

Joined Aug 2009

5K Posts | 62+

Sunderland

• Mar 9, 2011

• #4

Good idea Nob. I had to bleed my clutch last yr as it was engaging just off the bar

 

Batfastard

Joined Jul 2008

1K Posts | 0+

North Lincolnshire, UK

• Mar 9, 2011

• #5

Rusty

Are you bothering with the clutch on up changes?

If not, then it isn't the clutch. There are some reports that the detent spring in the gearbox is a bit weak on later models, but TBH I think this is a common problem on the Rotax.

Options.
Try the clutch bleed - it costs nowt.
Then there is the shift star thing, a gearbox upgrade, but unless you are happy pulling the engine covers off, not a DIY job.
Rear sets. Since I fitted a set of Griff's rear sets my gear change is as sweet as a nut. Liz's still hangs in neutral between some gears. No idea why it worked but it did.
Might even fit a set to Liz's bike yet.

 

rusty76

Joined Sep 2009

474 Posts | 1+

Leicester, UK

Discussion Starter
• Mar 9, 2011

• #6

Batfastard said:

Rusty

Are you bothering with the clutch on up changes?

If not, then it isn't the clutch. There are some reports that the detent spring in the gearbox is a bit weak on later models, but TBH I think this is a common problem on the Rotax.

Options.
Try the clutch bleed - it costs nowt.
Then there is the shift star thing, a gearbox upgrade, but unless you are happy pulling the engine covers off, not a DIY job.
Rear sets. Since I fitted a set of Griff's rear sets my gear change is as sweet as a nut. Liz's still hangs in neutral between some gears. No idea why it worked but it did.
Might even fit a set to Liz's bike yet.

Click to expand...

Cheers Paul

I only use the clutch on down shifts on the track but it was happening with both up and down changes. I also experienced that finding neutral is (even) more difficult than usual

I'll try bleeding the clutch as a first off (i've do the rear brake again anyhow....)

I'd really love some of Griffstar's rearsets as I'd also like the pegs a bit higher but the money's a bit of a stretch at the mo TBH

 

pinny

Joined Jan 2011

336 Posts | 0+

Near Coalville Leicestershire

• Mar 9, 2011

• #7

Funny you should mention that rusty, ive had a similar problem when shifting up but only in the higer gears. Mostly it seems to be when you are not positive enough.
And for the first time today it hapened on the downshift, just entering a corner, brown stains wernt far away i can tell ya..

 

Dynamo

Joined Oct 2010

446 Posts | 0+

Edinburgh

• Mar 9, 2011

• #8

I would also look at he chain tension

And maybe the oil, how old is it?

Worst case maybe the clutch is away

 

SUPERSTARDJ0

Joined Mar 2011

180 Posts | 0+

• Mar 10, 2011

• #9

Dynamo said:

I would also look at he chain tension

And maybe the oil, how old is it?

Worst case maybe the clutch is away

Click to expand...

This worked on my ZX but I also had to clean and grease the gear shift peg thingy also could it be the the selector rod things bent?

on http://www.apriliaforum.com/forums/showthread.php?t=9781

One guy has said "yeah
apparently its a safety feature that aprilia put into the bike. stupid if you ask me. There is supposed to be one inbetween every gear!
there not fun!!!".

Not sure if that's true especially if Griffs rear sets sort the problem out?

 

Batfastard

Joined Jul 2008

1K Posts | 0+

North Lincolnshire, UK

• Mar 10, 2011

• #10

DJ you are looking on the right forum for Tech stuff. AF1 is a goldmine, if it's been done it's on there.

However.

You are looking at the RS50 (moped) section. You need to look in the Aprilia 1000cc V Twins section, Tuonos, RSVr. Mille, Caponord, Futura and Falco's all run variants of the same engine, there is a wealth of material on gear change issues in these sections.

Chain tension is defo an issue - too tight and it will cause you problems.
If you want to do the Shift star thing read this POST

 

SUPERSTARDJ0

Joined Mar 2011

180 Posts | 0+

• Mar 10, 2011

• #11

God dam it, sorry guys didn't realise, wow do I feel like a tool.

 

Dynamo

Joined Oct 2010

446 Posts | 0+

Edinburgh

• Mar 10, 2011

• #12

When you changed the lever did you measure the distance on the pushrod, the bit you had to move over?

Seemingly it can make a big difference according to the apriameister griff

 

rusty76

Joined Sep 2009

474 Posts | 1+

Leicester, UK

Discussion Starter
• Mar 10, 2011

• #13

Dynamo said:

When you changed the lever did you measure the distance on the pushrod, the bit you had to move over?

Seemingly it can make a big difference according to the apriameister griff

Click to expand...

yeah I did. Clutch feels exactly the same as before with same bite point etc. I think that's good

I'm gonna change the oil and filter this weekend and check/adjust the chain/sprockets

 

Tifa

Joined Jul 2008

1K Posts | 26+

• Mar 11, 2011

• #14

rusty76 said:

It's not unusual for me to miss gears

Click to expand...

...any scousers near you?