12 replies to this topic

[tayto94]

Hi all

Having a bit of a prob on the sherco. I was using normal 2 stroke oil for a couple of weeks after i got the bike but got good quality fully synthetic oil and since starting to use it my low revs are bad. Its like the idle jet is blocked. It will bog if you snap the throttle low down which it didnt do before. Pull the choke out and it runs better.

I havnt whipped the carb out yet but question is can changing to fully synthetic or running the wrong mix give issues like bad low end. I mixed the fully synthetic at about 65 to one . . . too rich a mix???

Thanks

[t-shock 250]

You answered your own question about blocked idle jet!
Carb off and proper clean of the jets, then fully synthetic at 80:1 and away you go.

[rev3]

fully syn needs plenty of revs to burn correctly, go back to semi syn, I have always found this to perform better in both Gas Gas and my Beta.

I would be interested to know though who uses what.

[tayto94]

t-shock 250, on 23 April 2011 - 03:08 PM, said:

You answered your own question about blocked idle jet!
Carb off and proper clean of the jets, then fully synthetic at 80:1 and away you go.

It is going to a good clean but I was wondering if runnin too a mix of fully synhetic could lead to bogging, because it only started when I changed.

Looked around there and seen 80:1 as the proper mix for sul synt

[ormplus]

nothing wrong with using fully used ipone samurai for more years than can remember and never had a problem.as for bogging down on low revs, never heard of that one.

[geodet]

I had the same symptoms on mine.
A couple of rides ok then no pilot jet function. First check is to carefully unscrew and take out the air screw. I say carefully as there is a spring and washer attached which can become dislodged as you take it out. Look for any swarf around the rubber 'o' ring. A small piece of swarf will break the seal of the 'o' ring and cause your symptoms. At least that was what happened to mine.
Where does the swarf come from? No idea except to say I beleive it is poor manufacturing quality.
I dont believe changing your oil will cause these symptoms but for me 65:1 on fully synthetic is a touch too much oil. 80:1 seems to be what everyone runs.

Let us know what you find.

[tayto94]

Too the carb off at the weekend. Outside exhast side was completely covered up with gunk.stripped and cleaned jets and got rid of all gunk of outside. Put back together and removed petrol mixed at 65:1. Didnt get a chance to get her started up yet.

Got my workshed and bikelift sorted last weekend so going to give it a good going over this weekend - bearings,fluids,etc as hasnt been done since i got it.

will let ye know how it perorms after

Edited by tayto94, 28 April 2011 - 05:03 AM.

[tayto94]

Right, so just after taking the sherco for a bit of a run there now.

Had the jets all cleaned and changed the mix to 80:1

The boggy feeling when you snap the throttle open from idle is still there abit.
But now when i go for a higher speed run as it gets up th revs it completely bogs,it is not as bad i i back of the throttle but still there. . .

Should i strip the carb again or am i missing something?

Also noticed that a bit of fluid is coming out of the crankcase breather. just a drip

any ideas?

[tayto94]

seems to be fixed now. whipped the carb out andran through the jets again. dont think i got the main one right the last time. Took it for a good burn and the exhaust wa rightly smoking! id say from running the mix a bit rich there a good bit to bur off in there. will have to give it another good few hard runs to get rid of it

[Neo]

rev3, on 23 April 2011 - 05:31 PM, said:

fully syn needs plenty of revs to burn correctly, go back to semi syn, I have always found this to perform better in both Gas Gas and my Beta.
I would be interested to know though who uses what.

I've been running FS for some time too. But maybe it's worth buying a bottle of SS just to confirm your theory.
I was using SS a few years back but I wasn't really tuning my bikes much back then, so who knows, I might be missing something now. One thing I do not like about SS is that it eventually clogs up the exhaust. I know for sure my bike's much cleaner now days on FS.

Also, I had a friends 2002 Rev3 live at my place for a year or so. When it came emission and oil control I found that bike's engine to be dirty and disgusting, regardless of what oil or petrol we used ...even after we fitted a new muffler. And I've seen many Beta's that behave the same way since. That's just my experience but I could be wrong.

Best of balance.
Neo

[tayto94]

Cheers Neo,

It wasnt so much as a theory,just a thought. but the jets seem to have fixed my problem. I think I will stay on fully synthetic as its been recommended many times and quality wise its better in the long run

On another note, gave the bike a going over, trannie oil changed, went to repack the dog bone linkages, bearings fell to pieces!!!
think its time for a change!!!

[Neo]

tayto94, on 30 April 2011 - 10:17 PM, said:

On another note, gave the bike a going over, trannie oil changed, went to repack the dog bone linkages, bearings fell to pieces!!!..think its time for a change!!!

Wow ... but it sounds like that time came a couple of years back

Best of balance.
Neo

[tayto94]

Neo, on 30 April 2011 - 10:35 PM, said:

Wow ... but it sounds like that time came a couple of years back

Best of balance.
Neo

Thats the 2nd bike ive bought that when i check them they fell to pieces!!! (and ive only bought 2 trials bikes!!!)

Guess alot of people overlook them