LCGB Forums

Unfortunately my rear light lens decided to part company with the rest of the bike today. When I tried to put new screws in, they would not tighten and appeared loose. I have put some electrical socket holding screws in and they have 'taken' but again will not do up tight. Will I have to re-tap the holes or is this a common problem and there is an alternative sized screw, or does someone have a nifty tip? Thanks

The screws do vary in length and size, probably due to the different makes of rear light units.

I think the domestic electrical screws (M3.5) are 0.5mm bigger than the screws used in many rear light units, so they catch, but won't tighten up.

As David (above) indicates. there are many different types of rear light, so you many have to play with avrious screws before you get it wight.

buy a few different sizes off (ebay?), and see if something works for your unit. Try an M3 size for starters.

Remember, if the seller asks how long you want the screws, the correct answer is "I want to keep them"

Knowledge wrote:I think the domestic electrical screws (M3.5) are 0.5mm bigger than the screws used in many rear light units, so they catch, but won't tighten up.

As David (above) indicates. there are many different types of rear light, so you many have to play with avrious screws before you get it wight.

buy a few different sizes off (ebay?), and see if something works for your unit. Try an M3 size for starters.

Remember, if the seller asks how long you want the screws, the correct answer is "I want to keep them"

Sound advice

Tractorman wrote::lol:

Knowledge wrote:I think the domestic electrical screws (M3.5) are 0.5mm bigger than the screws used in many rear light units, so they catch, but won't tighten up.

As David (above) indicates. there are many different types of rear light, so you many have to play with avrious screws before you get it wight.

buy a few different sizes off (ebay?), and see if something works for your unit. Try an M3 size for starters.

Remember, if the seller asks how long you want the screws, the correct answer is "I want to keep them"

Brilliant!

I have some small metric taps,I will try them in my rear light tomorrow and let you know.

Thanks all. I’ve ordered some M4 screws but they have ‘button’ heads. If that size is too big, I may try the 3.5 and put some ptfe on the thread for a proper bodge

Well the M4s’ seem to be spot on. Nice and tight

1 1/2 x6 wood screws in my series 1 when I got it, the lens hadn't fallen off so a fix in some eyes

Buy some 3mm Rivnuts off the Internet and Araldite them into your damaged screw holes. Lots of people use these on damaged headset screw threads for the chrome rim ( myself included on my Li Special ).

Yes
3mm rivnuts!!!!!
did this myself last week. best ever fix!
drill holes out with 4.5mm bit, possibly 5mm bit.
then gently tap in the rivnut from the rear of light housing.
job done.
(alloy rivnuts)
use original 3mm screws.

lam1962brettagg wrote:Yes
3mm rivnuts!!!!!
did this myself last week. best ever fix!
drill holes out with 4.5mm bit, possibly 5mm bit.
then gently tap in the rivnut from the rear of light housing.
job done.
(alloy rivnuts)
use original 3mm screws.

I think sticky has a section on this fix in the new edition.