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SteveD wrote: ↑Thu Feb 11, 2021 8:57 pm I've read recently that the recess where the starter is seated, top rear of the casing, can have a small deformity that might allow the starter to sit nqr in position. That might lead to the open starter nose to crack. Might be worth having a quick look before putting it in.

Can anyone else confirm this?

gspd wrote: ↑Thu Feb 11, 2021 5:40 pm 1- Make sure the new starter has the same number of teeth as the old one.

2 - You don't need that front bracket anymore

Zombie Master wrote: ↑Fri Feb 12, 2021 3:49 am

SteveD wrote: ↑Thu Feb 11, 2021 8:57 pm I've read recently that the recess where the starter is seated, top rear of the casing, can have a small deformity that might allow the starter to sit nqr in position. That might lead to the open starter nose to crack. Might be worth having a quick look before putting it in.

Can anyone else confirm this?

I will. Is the deformity near the nose of the starter in the crankcase?

The upgraded Valeo's, with the clips for the magnet structure, are OK....and, at least in the USA, are much cheaper, and seem to hold up just fine over lots of miles. There can be interference problems when fitting a Denso or Valeo starter to a bike that previously from the BMW factory had a Bosch. If you have one of the engine blocks with the problem, you can cause problems unless you fix it, and the fix is pretty simple. You do NOT want to break the nose cone of your new starter. There can be a Denso interference problem too, and the below article describes the interference problems for both Denso and Valeo, with photos of both situations. You'll have to scan the entire article.

Zombie Master wrote: ↑Fri Feb 12, 2021 3:40 pm Yes thank you for making me aware. Since my bike did originally come with the Bosch I'm concerned.
So I'm a bit worried about using this new starter. Sounds like bikes that came with the Bosch starter may need to have some metal work in order to fit a Valeo. Looks like some filling can correct it, but getting it wrong could cause the nose of the starter to break. This could damage the flywheel. Again I fail to learn my OEM rule.

From Snowbum:
"The starter might not fit perfectly, may not want to go fully downwards at the nose area & the Valeo threaded bolt holes (or even Bosch unthreaded ones??) may not line-up perfectly. Inspect carefully, & use a half-moon fine file, or a small electric rotary tool of some sort, to make this inside area smooth at the top, with NO metal that is 'proud' (or of lesser diameter, causing a reduced diameter). You can feel this with a fingertip, and usually see it with your #1 eyeball. I have personally seen this and had to remove about .020" (+-), on both sides, at that top area. This is easy to do, & then the Valeo (Bosch?) should fit & mount correctly."

As I read about this subject, I'm hearing more warnings about aftermarket starters.

Maybe time to tear into the original starter and find out how returns are done on Amazon.

How does the nose drive gear mesh with the flywheel

• The drive pinion is on a drum which slides on splines on the drive shaft. (Note. on a Valeo starter the drive shaft isn't the commutator shaft, there is a planetary gear set to increase torque and reduce speed between the two)
• The drum includes an overrun clutch so that the engine won't drive the starter motor if the starter is kept engaged too long.
• The clutch is moved away from the body by a forked lever that runs in a groove on the drum. The other end of the lever is attached to the solenoid slug.
• When the solenoid is actuated, the slug moves backwards (away from the flywheel) so that the lever moves the drum forward (towards the flywheel) bringing the gears into engagement.... a spring moves it back out of engagement when the solenoid is released.
• In contrast to an inertia starter, the gears are engaged before the motor starts to turn.
• The teeth on the drive pinion and those on the flywheel are chamfered to ease the engagement of the two gears.