Flat Slide Carbs.

[Paul T]

Does anyone know the real advantage these carbs make over CV's, I'm a not sure weather to upgrade or not as some of the fastest laps on the Radical web. site are from 2001? A further enquiry is the SR4 running injection or Carbs?

[nildram]

The 2001 times are either wrong (haven't been updated) or we haven't raced on those circuits since. Lap records have been obliterated over the last couple of years. Having said that, some were running with flat slides in 2001 anyway. I believe they give up to 20 or more bhp (taking ram air effect into account) over the CVs. However, I'm told they make it trickier to get off the line.

As for the SR4, flat slide carbs.

[Paul T]

Thanks, looks like I may have to raid the piggy bank then!

Any idea as to why no injection on the SR4?

[alec dudfield]

I'll have a fiver with you that the SR4 ends up fuel injection Adrian...

[nildram]

I wouldn't complain if it did (except for the additional cost). Should have mine by tomorrow's test!

[jedi]

Flatslides do increase performance, but I doubt by 20hp. They drink more fuel and can make the engine a pig to start. Dont pay more than 1200pounds for them new.

[AL001]

Any tips for getting flat-slide carbs going if unused for a few months?

My Radical starts no probs when used regularly but has been in storage over winter and last time was reluctant to start with normal technique of 2-3 prods then a 1/4 gas.

Will be taking to the road/track again soon and the easier it starts, the better.

[TonyF]

Couple of pumps then start, if its reluctant floor the throttle whilst turning it over until it starts. Make sure you have a good battery on !!

[victormeldrew]

CV carbs rely on vaccuum to pull open the slides, and will never react as quickly to sudden throttle changes as slide carbs, where the carb slides are attached directly to the throttle cable. For similar reasons they (CV's) will almost always be more economical.

For a given size, the CV will not flow as much at full throttle either - there will always be some restriction from the butterfly even when fully open.

Memories of highly tuned 2 strokes with big bore Mikuni and Lectron flat slides, with bores so large you could see the pistons! Happy days.

>> Edited by victormeldrew on Tuesday 30th March 19:46