10 replies to this topic

[Sherco250cc]

Hi I was wondering what jets,needle etc you are all running on these carbs as I cannot get my 2010 290cc sherco to run properly at all with it and it is proper doing my head in!!! any help is much appriciated Many thanks Tom

[copemech]

Sherco250cc, on May 19 2010, 04:32 PM, said:

Hi I was wondering what jets,needle etc you are all running on these carbs as I cannot get my 2010 290cc sherco to run properly at all with it and it is proper doing my head in!!! any help is much appriciated Many thanks Tom

I am not quite sure just how popular these things are becoming. Seems mainly the top lads running them.

As they still seem very similar to the stock carb, many of the same principals should apply. So what jets are you running? Where did you source it? Does the seller have recommendations? Possibly you just have a new carb with mfg slag that needs cleaning?

I think Splatshop sells them, might call, and if you are lucky, maybe MRS knows something they will tell. Probably most settings will be for a 290, not a 250, yet should not make much difference.

Symptoms?

Edited by copemech, 20 May 2010 - 04:05 AM.

[clav3]

I've been told by the Aus dealer that the red Dellorto goes hand in hand with the 300 top end that only fits the 2010.

The carb and top end package costs about $1800.

[tricky dicky]

Good luck trying to get it running right. I spent hours and hours trying to get it running right and gave up and just put the standard one back on and it runs perfect. You can try contacting Splatshop about it or MRS but the carbs supplied by MRS are modified by Paxau and nobody knows what has been done to them. In the SSDT the bikes with the red carbs were having major carburation problems and that included Cabestany's bike so good luck!

[Sherco250cc]

Hi i have been using the standard dellorto carb until I tried the red dellorto,
I got the carb off a scooter website based in germany mega cheap so thought id give it a shot,
it was the same as the dellorto VHST 28BS but red that was on splat shop,
but its probably jetted for a lambretta scooter and not a sherco haha they look mega trick!!!
I didnt know that paxau had moded them like wish id of known before,
With jets around the same as the standard it should be alot better was qhite surprised it felt alot smoother with it on but yet a slight power increase it ran fine for around 15 mins and then started to choke up, the same as what my keihn did when I tried it apart from this didnt just bork out.

Many thanks Tom

[sirhc]

After messing with the VHST on my Sherco Access on and off for a couple months I finally ditched it for the standard Dellorto. No matter what I did I couldn't get it to run clean without pinging and I tried everything! It has a little less power with the round slide, but runs much better. One of my customers that got the Access put an OKO on and is now also much happier.

[copemech]

Take the red rattlecan(Krylon) to the stocker and you will likely look and ride better!

Gasgas tried the VHST several years back it seems, but went away from them, problems roumoured. They were selling them as a replacement for the troublesome Mikuni's on the Beta's with some reports that they worked well.

I cannot fathom why one would run ok initially then go downhill unless there was crap in it.????

I cannot fathom putting a 28 on a 250 either, as if you really need more power, why did you buy a 250 rather than a 290?

The Kiehin(or OKO) is still a better mixer, yet more finiky! Take your pick on the OKO- 24-26-28-30mm!

Long story made short, sounds as though I shall refrain from that experiment untill Paxau calls me with a solution and hell freezez over.

[sirhc]

Quote

I cannot fathom putting a 28 on a 250 either, as if you really need more power, why did you buy a 250 rather than a 290?

My 2.5 Sherco Access did come stock with the 28mm VHST. I agree, I think that was a lot of the problem I was having with the carb.

I just put a 24mm OKO on my son's 2010 125 (with good results) so I then stuck the 26mm off the 125 on my 250 and all is well now

[copemech]

sirhc, on May 20 2010, 11:19 PM, said:

My 2.5 Sherco Access did come stock with the 28mm VHST. I agree, I think that was a lot of the problem I was having with the carb.

I just put a 24mm OKO on my son's 2010 125 (with good results) so I then stuck the 26mm off the 125 on my 250 and all is well now

Oh, btw Chris, I think I just missed meeting you in OK? I seen Ty's bike and such on Sunday when I came up. Was BS' ing with the PA guys just behind there in the pits, yet did not see you if you were there?

MC

[sirhc]

I was there, I was just hiding from you

[Marlintec]

Hi all,

The Dell'Orto VHST is very sensitive to float level, much more than standard PHBL. The first batch of VHST carbs were prone to fail at the level-valve, then caused the bad reputation when the GGPro (280) appeared in 2003. After that, the factory re-designed the level-valve system and the carb worked well when properly jetted.

I have a unit of the first batch (actually designed for the Cota 315, when Dougie were riding it) and found a better stability when I increased the lenght of pilot jet, allowing to aspire gas 4 mm deeper in the vase (details in http://www.terra.es/...rlintec/taller/ )



I wonder if the new configuration of Sherco 2010, with a fuel-pump could affect adversely to the level again?

Cheers,

JM.