Repop Selector Key Failure – Sachs

[Ernie Phillips]

http://s250.photobucket.com/albums/gg276/ernie7711/?action=view¤t=P4230116.jpg

We have recently (Ocala & Diamond Don's) had multiple failures of Repop Selector Keys. The linked photo (item E) shows a failed key (Christopher's Six Day – Ocala).  To add insult to injury, the failed key locked the gearbox and broke both drive and driven gears.  While leading moto 2 at DD, forth gear - full song ... my bike locked up.  Just prior to failure, my shifting became a little quirky (key failing?).  Two shifts later, I was side-lined with a locked up gearbox.

What I want to know is:
1. Anybody else had a failure like mine?
2. What is the common failure mode (tip wear, complete failure, other)?
3. Anybody got a NOS key they are willing to part with?

I don't purposely abuse my bikes, but I ride hard.  On occasion I miss a shift -- engine over-revs and when a gear is finally engaged, additional stresses are put on components.  I do not consider this abnormal use  --- it is a competion bike.  However, I am unwilling to go on breaking gearboxes.   I believe my failures are due to sub-standard repop parts which may be fine for trail riding but not for racing.  I'm going to try one of JP Morgen's 4340 keys.  Seeking suggestions and ideas to make a bullet proof gearbox.  Any and all help appreciated.


Ernie P.
Chattanooga, TN

[gooddirt]

I know a few others that have had the trans DESTROYED!! with those same keys. Only good use for them is on a bike that sits in the garage. JP can set you up and talk to him about the gear Mods as well. LG

[sixdazed]

Is there a way to tell the repop from an oem?I have several new ones sitting here that i am now paranoid of using[V].Yikes,
                                                           Ric

ric emmal

[OUCWBOY]

Ric,
The originals seem a darker color and not as glossy.

Donny Smith
Paragould, AR

[VICTOR MONZ]

I have just began riding a fresh Six Day with JP's set-up and it shifts like my RM 125....smoooooth !

So far so good.  Nice machine.  It will be put to the test this weekend.

Victor

[Ernie Phillips]

Another one bites the dust:

http://s250.photobucket.com/albums/gg276/ernie7711/?action=view¤t=P5050015.jpg

Photo of failure of key on 50v as identified in original post (Diamond Don's 2008).  Appears similar failure to Christopher's (tang breaks off at hub junction).  On this failure, the broken tang jammed between gears.  2nd gear on layshaft and tang had tremendous battle.  2nd gear was big looser – several teeth shucked off.  A broken key is bad enough, but when it causes so much secondary damage ... disappointed and discouraged  
Our two running race bikes with repop keys will remain parked until upgrades are preformed.  Pay me now or pay me later -- racing with repop keys is too expensive.  One bike will get NOS key (thanks Donny S) and one will get HT 4340 key (thanks JP Morgen).

Ernie P.
Chattanooga, TN

[OUCWBOY]

Ernie,
I have a few nos gears and a couple used engines if you need anything.
Donny

Donny Smith
Paragould, AR

[Gavin Housh]

I had two keys fail in two engine builds. The black keys are for garage use only. The NOS keys have a greenish grey hue. Don't be fooled. Big $$$$$ loss. Good luck?

[Ernie Phillips]

Take the test.  Identify the bullet proof selector key:

http://s250.photobucket.com/albums/gg276/ernie7711/?action=view¤t=P5080029.jpg

Ernie P.
Chattanooga, TN

[Doug Wilford]

Ernie;
I can't tell which key is NOS unless I can see a side view.  NOS keys have a slight groove around the ends of the keys where the narrow part of the key ends.  Plus the camfer as Dane mentioned.