BlatChat comes to the rescue once again, and directs me towards a different approach... Yep, this time with the wing mirrors.
Fitting the wing mirrors is one of the tasks Caterham recommends doing towards the end of the build, and I've genuinely reached that stage. The finish line is within striking distance. Tackling the mirrors on the surface appeared to be straightforward however it was soon derailed and went in a different direction.
Firstly let's talk about the standard wing mirror Caterham ships with the car, I'm not sure which parts bin they were found in but they're awful. They aren't retro and they aren't lightweight. They're just crap, sorry but they are! Long term they are to be fitted to the full doors, but from my own experience and comments of others when fitted to the door they vibrate so much the image in the glass is next to useless. Though that's secondary to their cosmetic challenges. In order to pass UK IVA, you need to fit the mirrors to the side of the windscreen which requires modifying the mirrors in a manner which can be reversed. Since I'd planned to submit the car for a Manx test this step wasn't required and I planned to fit straight to the full door.
The fitment instructions for fitting a mirror to a door states there are two holes within the metal window frame under the vinyl door material. Once located you need to drill through the vinyl and bolt the mirrors onto the door frame. I couldn't locate the holes, so I turned to BlatChat to see if the door design had changed, and Caterham's instructions were out of date, which wouldn't be the first time. The response I received was "No!! Don't drill the doors!", I jest, but the general view was I would regret drilling the doors and there were better solutions, along with better mirrors. The BlatChat regulars commenting on this are pretty much right most times, so I took their comments seriously and started to look at their suggestions.
In the end, I've ended up buying parts for two setups, one for immediate use where I attach the mirrors to the windscreen, second where I attach the mirrors to the door but without drilling. Both solutions will use new mirrors and mounts.
This blog will cover the windscreen mount option only, as parts for the door option are expected to take longer to arrive plus I need to talk the wife into letting me buy carbon mirrors too!
Before we get into the solution, I want to make it clear credit for the solution goes to the regulars on BlatChat, and a notable mention to Collidog for supplying details from his install.
You might be wondering why two setups. Simple! I want to have mirrors permanently attached to the doors, but also easy support for mirrors when the doors aren't attached, this solution provides that. It's important on the IOM where there are so many bikes on the roads.
Fitting is very straightforward so there isn't need for a detailed install blog.
For the windscreen option I went with Racetech Single Seater mirrors supplied from DemonTweeks, with convex glass and a black finish. The mirrors are sold separately at approximately 27GBP each. A fitting kit is also required, at 15GBP, but only one is required as it contains fittings or both sides.
The kit consists of a mounting base which is attached to the windscreen using the middle screw/bolt hole, the existing countersunk screw needs to be removed. The mounting base has a hole through the middle for the securing bolt to pass through and a rubber pad to absorb vibration. The rubber pad sits between the car and the base. The outer top edge of the base is threaded, onto which the mirror stalk and mirror is screwed and secured. The mirror is on a spherical fitting which tightens against the base once secured and subsequently holds the mirror in position. The mirror part is shipped with some additional fitting options which need to be removed before fitting.
So fitting is very straightforward, the only aspect to watch out for is the mounting bolt length. The one shipped is too long for the screen and needs to be cut down, or you run the risk of cracking the screen. When measuring and cutting my bolts I forget to take into account the countersink on the original fitting, so ended up with a bolt which was too shallow, as a result I've had to order some additional, I've gone with M4x20 Cap head screws. I didn't repeat the mistake so did manage to get at least one mirror attached, whilst I wait for the replacement bolt order.
What's particularly nice about the solution is that the mirror can be removed when doors are fitted and the small mounting base left, though for complete compliance it might need a rubber cover.
Mark, I bought these Race Tech Mirrors to fit to my Supersport and like you made a mess of cutting one of the Cap Head Screws, so I ordered some M4's as you stated, but in actual fact the size is M5, so you may wish to correct your article. Now I am struggling to find a Small Cap Head M5 x 20 with a 7mm head width. Please could you tell me where you bought yours?
Going to do this soon. I saw the fixing bolts supplied were 28mm long. Best cut to 18mm best or 20mm to fit base the the stantion to fix Racetech mirrors