Jump to content
Click here if you are having website access problems ×

Calling R400 owners- bunny hop survey


Nick W

Recommended Posts

Hi all

 

Took delivery of my R400 6 weeks ago and have racked up c3,500 miles to date including some pretty awesome roads in France *thumbup* *thumbup* and a track day at Brands. It's fabulous fun and certainly a little faster than my old standard roadsport 😬. Grip is preposterous and acceleration highly amusing.

 

I only have one gripe- the mapping (seems to be a hot topic at present).

 

To begin with there was no power between 2,500-3,000 rpm. Following a chat with Caterham they altered the map on its 500 mile service. Apparently the original map was a combination of the race map with a sort of SVA friendly patch stuck on the front for emissions.

 

Flat spot has now gone, but in it's place has come a random degree of "hesitancy". When giving it a bit more gas below 4,000rpm sometimes it picks up cleanly, but often it doesn't. This leads to highly irritating bunny hops. You have to be quick on the clutch.

 

Now I know this is a high performance Seven and I should be thrashing its nuts off etc etc, but low revs are unavoidable eg. in built up areas or around hairpins. It's v. annoying not being able to get back on the power smoothly as it completely upsets the car's balance in the corner *mad*. It also makes you look like a pillock (especially aeroscreened and helmeted up outside a pub full of bikers like a few weekends ago 😳).

 

To be fair Caterham are looking into this and think it's caused by the ECU shifting between the "2" maps and are working on a fix. They also said a number of other R400 owners have reported a similar experience.

 

So other R400/ R300 owners- are you having the same problems?

 

Interested to hear how things are going.

 

Happy blatting

 

Nick (aka Bunny Hop King)

Link to comment
Share on other sites

While the performance fault sounds like a classic mapping problem and something that frequently has to be dealt with during car development - rather than by the owners - during drivability testing, i have had a couple of cases of your bunny hopping after fitting a new clutch and can confirm it only happens at the most public spot - town centre pedestrian crossing in my case. My dta unit map has been fine for 2 years but with a new clutch as the only change the take off charactoristics changed significantly and I'm not sure that I can correct it be map tweaking. Are the R400s all fitted with race clutches or the same as previous Roadsport models?

Caterham have one hell of a problem in finding a map that will satisfy emissions and the requirements of L7OC members and I cant see how they will manage this trick with the present generation of engines when the rules for 2005 come into force. Engine design is now so constricted by emissions that it can't really be a lot of fun unless you can work in unregulated motor sports

May be those of us with amateur built pre-SVA cars should hold onto them as they may be the last road running sports cars that we will be legally able to alter

 

Link to comment
Share on other sites

Keep on at them. It is a dead simple mapping problem and it strikes me that Caterham act like a bunch of amateurs in this regard. Insist on them telling you the version number of the map and ask who else of the R400 owners have the same version. Ask which version the press car was running. Get them to shape up.

 

It is an easy matter for Caterham to deal with this professionally. A lack of effort from Caterham should not be an option.

Link to comment
Share on other sites

I must admit upto now Caterham have been quite helpful recently with my problem. I could only put it down to a mapping problem, it did take 30+ phone calls and a letter to Simon Nearn to get action, but now they are sorting it all out and going beyond the call of duty.

 

My advice is to make sure you talk to Jez as he seems to be able to get things sorted out.

 

See X777CAT here

 

Link to comment
Share on other sites

Simon- Have only made c10 calls so perhaps I need to get the redial button working! What's up with your car? (R300 isn't it?). Will try Jez.

 

Peter- Completely agree with you! Especially since it wasn't the cheapest purchase I've ever made.

Link to comment
Share on other sites

This is faintly ridiculous.

 

Starting from scratch with no map whatsoever on Thursday night at 10pm, I had my R300-equivalent engine running well enough to drive by midnight. It felt a bit sluggish at some points in the rev range which I observed on the drive up to Cadwell so I rejigged the fuelling before going out on track where it performed "adequately".

 

"Adequately" meaning bloody brilliant 😬

 

None of this was done with the benefit of a rolling road or a dyno, although I was not subject to emissions constraints. But it was dead easy.

Link to comment
Share on other sites

I've wondered about Adams last question for a while also.

 

I was probably the first "R400" to be run at pace on the road since i ordered an SLR for various reasons which have been discussed previously and may be again soon on Chit Chat that could run at altitiud. Well one that could sense changes in barometric pressure continually unlike MEMS

 

Well i also have done some 3700 miles and 10 days ago took my MBE to be upgraded from the race map to the new R400 map. Here is my response to the new map to Nathan yesterday.

 

Hi Nathan

 

Thought I would drop you a line regarding the new R400 "road" map you kindly installed onto the ECU 10 days ago.

 

Its difficult to describe some of these things and i will be happy to speak over the phone and be more specific if you wish. 01267 267133 or 07887 571911

 

The lack of a "choke" effect on start up on the race map has disappeared. Instantly noticed this.

The new map also seems "quieter", "smoother", "freer" and revs smoothly from lower down the scale.

Not been able to try this map flat out at the top end but did see of an 900 Ninja this afternoon!

However

 

Engine cuts out for split second if revs are constantly around 2750 (now remember I'm reading from the tacho and when we set the tick over I was over reading by say 100 rpm. So the figure above in all reality is say 2650rpm) and the picks up again. I have tried to make this happen and it will basically do this every time.

Again if running in traffic at 3100 the engine runs very lumpy/rough. Not spluttering but it just does not like it.

With both the above if you are accelerating through the revs both are invisible. But once you know they are there it actually makes driving in traffic or through speed limited areas very uncompfortable. It has made me look for other bugs or glitches.

Far more pops and bangs on over run. I like this of coarse but feel its to much really. (Could this be as we have set the idle higher or is it the map?)

Most of all though the sheer ("BANG", "whoa!!!!" "smile", "shiiiiiit") guts has gone from the map/engine.

It is significantly smother revving but in some respects it has become more undriveable because of the bugs. The original map is not that rough low down. It may not feel as if it likes going slow with the race map but you knew what was under your right foot !!!!!!!

 

I hope this does not sound to much of a criticism. But given a choice of the two maps even though you say the new map has more BHP and may when "driven" be smoother/faster the race map is more predictable/punchy and fun.

 

I don't know if you would be able to combine the tow maps but to sell a car I know which map is more impressive.

 

Until you have refined the map is there any chance we could catch up with each other at the festival and re-map to the race config. I realise you may well be very busy there?

 

I will be there on Saturday.

 

If not I will be at the Club Track day at Llandow the following weekend and so will be able to make further comments having driven the car whilst (as my mentors say) I give it some welly!

 

Look forward to your comments or call

 

Simon - MY 51VEN - SLR440

 

 

MY 51VEN - SLR

Give it some WELLY!

Link to comment
Share on other sites

Dave would be happy to supply Caterham !

 

Regardless of opinion, you can't alter the fact that Mr Walker has mapped over 200 K series in all states of tune - he is to K tuning what "Yoda" was to Star Wars! Why miss out on this?

 

I'm sure there is a good reason but to a simple man like me it does make a lot of sense to use the most experienced people.

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...