Catrerhams and Speed Bumps....

[MikeGF]

Hi all

Bit worried about my Superlight. Seems to ground out on every speed bump I find. Even the smallest speed bump causes a scrape on the underside of the engine.

Is this common, or is my adjustable suspesion set too low? Is there a special knack I need to learn?

Cheers
MikeGF

[fergus]

MikeGF said:

Hi all

Bit worried about my Superlight. Seems to ground out on every speed bump I find. Even the smallest speed bump causes a scrape on the underside of the engine.

Is this common, or is my adjustable suspesion set too low? Is there a special knack I need to learn?

Cheers
MikeGF

Go over them diagonally. I am going to make up a nylon block to go under the cross at the front of the engine, which will be at the same height as the base of the sump. This should stop the front of the dry sump pan getting worn away. If I machine a 'cross' into a nylon block, I can then use some exhaust U bolts to secure this to the chassis. Will make a prototype in wood.

A really simply way to do this is to use one of those opaque plastic chopping boads, and drill and zip tie this in place to stop the sump taking a battering.

[Piers917]

I've never had a problem with my Superlight. You may want to get the ride height and rake checked Mike. IIRC it there should be about 65-70mm of clearance under the sump, and about 15mm rake front to rear. Your best bet is to do a search on Blatchat.

Piers

[MikeGF]

Piers - I am somewhat of a mechanical numpty, but learning...
The sump does seem to hang low under the car, will check tonight, so about 65-70mm is the norm.. Its going back to Caterham in a week or so to fix the speedo which doesn't work so i'll get it looked at then.

fergus - that sounds like a good plan, will think about that myself let me know how it goes.

Also, haven't sent of my club membership yet so can't search blatchat, must do it today..

Cheers
MikeGF

Edited by MikeGF on Wednesday 12th March 11:26

[CanAm]

Mike, I'm pleased to say that you CAN search Blatchat without being a member, you just can't post or reply to a topic. You can however send a PM to anyone by clicking on the little icon on top of each post.

As for ride height, a tip from a L7GB Club Member:-
"Hmm, for road use I set mine up so that a coke can will roll under the sump but a wine bottle won't. Very unscientific but these were the tools that were to hand at the time ."

[MikeGF]

Thanks CanAm, never knew that, will have a search

I'm intrigued, and really want to try the coke can/wine bottle trick. I only have beer at home so it's a good excue to have one of those, and get the wife to finish the wine Any excuse..

Cheers
MikeGF

[Stickshifter]

I have an R400 and never have an issue with bumps or drive entries....my Porsche does, Caterham never...

-S

[CanAm]

See another post from Mike. He only had 45mm clearance under the sump
Alan.

[bikemonster]

45mm clearance? Luxury!

I recently had a Toyota 4AGE 20 valve engine installed into my 7 replica. I now have 25mm clearance.

Surprisingly I managed to drive it back from the workshop without tearing the sump off.

Unsurprisingly I am having a custom sump made up which will allow me to drive over pieces of thick paper with impunity.

[RobM77]

MikeGF said:

Hi all

Bit worried about my Superlight. Seems to ground out on every speed bump I find. Even the smallest speed bump causes a scrape on the underside of the engine.

Is this common, or is my adjustable suspesion set too low? Is there a special knack I need to learn?

Cheers
MikeGF

1) This is a standard superlight with a non-VVC k series engine I presume? The VVC engine has extra gubbins on top and has to be mounted lower, thus creating sump clearance issues.

2) How fast are you going over speed bumps? Even with my previous VVC Roadsport if I went really slowly (about a quarter walking speed or around 1mph) speed bumps weren't a problem. I only caught the sump once, and that was leaving Bedford Autodrome where they have especially evil little ones.

3) If you're going very slowly and still catching the bumps then yes, your suspension may be set lower than standard. It could have been adjusted by the previous owner, or for example he/she may have fitted 13 inch wheels to a car originally set up for 14s. Caterham will hopefully tell you the standard ride height over the phone and where to measure it.

HTH

[MikeGF]

RobM77 said:

MikeGF said:

Hi all

Bit worried about my Superlight. Seems to ground out on every speed bump I find. Even the smallest speed bump causes a scrape on the underside of the engine.

Is this common, or is my adjustable suspesion set too low? Is there a special knack I need to learn?

Cheers
MikeGF

1) This is a standard superlight with a non-VVC k series engine I presume? The VVC engine has extra gubbins on top and has to be mounted lower, thus creating sump clearance issues.

2) How fast are you going over speed bumps? Even with my previous VVC Roadsport if I went really slowly (about a quarter walking speed or around 1mph) speed bumps weren't a problem. I only caught the sump once, and that was leaving Bedford Autodrome where they have especially evil little ones.

3) If you're going very slowly and still catching the bumps then yes, your suspension may be set lower than standard. It could have been adjusted by the previous owner, or for example he/she may have fitted 13 inch wheels to a car originally set up for 14s. Caterham will hopefully tell you the standard ride height over the phone and where to measure it.

HTH

Hi Rob

1 - It's the standard 1.6 Superlight
2 - Regarding speed - I literally have to inch over, then scrape, then carry on as normal. which can take a while depending on the bump. I have to plan routes carefully so as not to hit any biggies!
3 - The car has 13's and were the original fit, so maybe ot wasn't a problem for them?

The car os off back to Caterham shortly to have a warranty fix (the speedo doesn't work) and I am going to ask their advice, for practicality (never thought I would say that for a Caterham ) I need a bit more clearence.

Cheers
Mike

[RobM77]

MikeGF said:

RobM77 said:

MikeGF said:

Hi all

Bit worried about my Superlight. Seems to ground out on every speed bump I find. Even the smallest speed bump causes a scrape on the underside of the engine.

Is this common, or is my adjustable suspesion set too low? Is there a special knack I need to learn?

Cheers
MikeGF

1) This is a standard superlight with a non-VVC k series engine I presume? The VVC engine has extra gubbins on top and has to be mounted lower, thus creating sump clearance issues.

2) How fast are you going over speed bumps? Even with my previous VVC Roadsport if I went really slowly (about a quarter walking speed or around 1mph) speed bumps weren't a problem. I only caught the sump once, and that was leaving Bedford Autodrome where they have especially evil little ones.

3) If you're going very slowly and still catching the bumps then yes, your suspension may be set lower than standard. It could have been adjusted by the previous owner, or for example he/she may have fitted 13 inch wheels to a car originally set up for 14s. Caterham will hopefully tell you the standard ride height over the phone and where to measure it.

HTH

Hi Rob

1 - It's the standard 1.6 Superlight
2 - Regarding speed - I literally have to inch over, then scrape, then carry on as normal. which can take a while depending on the bump. I have to plan routes carefully so as not to hit any biggies!
3 - The car has 13's and were the original fit, so maybe ot wasn't a problem for them?

The car os off back to Caterham shortly to have a warranty fix (the speedo doesn't work) and I am going to ask their advice, for practicality (never thought I would say that for a Caterham ) I need a bit more clearence.

Cheers
Mike

Everything checks out there, so you're taking the next logical step, which is to ask Caterham's advice. Let us know what they say!