Author Topic: VX800 Scrambler  (Read 2058 times)

Offline Michael Star

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VX800 Scrambler
« on: June 26, 2018, 07:41:19 AM »
Hello all,

so here is the new project VX800 Scrambler, few mods already in place
- gaitors
- chrome paint on the front fender
- Corbin seat
- Michelin Anakee 2 in back
- Michelin Pilot Sport 3 front

Few more mods planned
- handlebars
- hand guard with DRL
- mini puig shield
- folding mirrors
- LED incidators front + back
- racing plates + number
- tail tidy

the progress is nice and good, however the bike runs on one cylinder only.  The front tone is cold, I know this seems to be a common issue and would appreciate any help how to find the root cause
- fuel pump ?
- carbs ?
- air?
- spark ?

Can you point me in the right direction?

Offline Michael Star

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Re: VX800 Scrambler
« Reply #1 on: June 28, 2018, 02:39:44 PM »
Right. Problem solved, it was an faulty fuel filter.
Bike is now running, bit rough.
Front cylinder is defo more hot than the rear one
Will see if carb balancing carbs will help.

Offline Michael Star

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Re: VX800 Scrambler
« Reply #2 on: July 05, 2018, 05:28:03 PM »
Another nice evening in NL.
Changing handlebar and ignition lock to match the tank.
That is done, only took like 4 hours.
Planned over the weekend
Drl lights
Hand guards with led indicators
Flash relay
New grips
Wind shield
Paint few brackets black.

Offline ErTussenDoor

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Re: VX800 Scrambler
« Reply #3 on: July 06, 2018, 02:54:33 PM »
You have been quite busy!
Interesting to see where this is going.

Btw, I am looking for a standard handlebar, do you want to get rid of the original one?

Andre

Offline Michael Star

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Re: VX800 Scrambler
« Reply #4 on: July 07, 2018, 04:58:04 PM »
Hello Andre, sure happy to post.
Item is based in NL. Where abouts are you?
By any chance do you have rear luggage rack?

Offline ErTussenDoor

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Re: VX800 Scrambler
« Reply #5 on: July 08, 2018, 04:58:48 AM »
I am in Eindhoven,

Also have a rack, I was planning to sell it on Ebay, but I am sure we can work something out.

I will send you a PM

André
(tried to upload a picture, but can't get it to accept my pics  :huh: )

Offline Michael Star

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Re: VX800 Scrambler
« Reply #6 on: July 08, 2018, 07:01:52 AM »
So another 7 hours and few bits progressed
Handguards with Led on, working
Wiring for DRL done
Paint is drying.
Mirrors are back on.

Offline Michael Star

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Re: VX800 Scrambler
« Reply #7 on: July 08, 2018, 11:53:00 AM »
Another few hours and progress is seen, front end is almost done
Puig fly screen
Black head lamp brackets
Black head lamp body
Wiring installed
Drl switch is in.
Drl are converted from the original indicators with addituon of smoke lens

Time for back end.
Spend few moments cutting out the fairing, not sure yet where i want this to go.
« Last Edit: July 08, 2018, 11:54:59 AM by Michael Star »

Offline Michael Star

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Re: VX800 Scrambler
« Reply #8 on: July 09, 2018, 04:25:13 PM »
Ok, the saga continues. Bike started to run erratically.
Took the tank off, no fuel in the front cylinder.
Think it might be the fuel pump.
Filled up  with petrol, it runs better but under acceleration it is a bit rough.
Seem like next job is to clean carbs and the fuel pump.
Bugger was hoping for riding coming weekend.

Offline ErTussenDoor

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Re: VX800 Scrambler
« Reply #9 on: July 10, 2018, 02:29:07 AM »
The rear doesn't depend on the fuel pump. The front needs the pump when the fuel level gets below a certain point. So you are probably right with the pump.
Also make sure the vacuum hose from the pump is properly connected to the front inlet manifold .

André

Offline Michael Star

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Re: VX800 Scrambler
« Reply #10 on: July 10, 2018, 03:36:29 AM »
Hi Andre,
yes thank you very much. The rear curb is fed via gravity, that one is OK. The front one is getting hardly any fuel.

so after this morning ride can confirm that the rough running is due to the fuel starvation to the front cylinder.

Symptoms:
Adjusting Air / fuel screw -> this needs to be 2 turns + 1/4 out for the bike to run half decent
Rough acceleration.
Running on one cylinder, when the front carb is under the fuel level (around after 13 l are gone) . Switching to reserve does not help to.
The front cylinder bowls were empty.

Fuel pump operation check:
I have removed tank
I have disconnected the fuel line to the front cylinder
I have hooked a supplement line of fuel from plastic bottle.
Start cranking the engine.
There is no fuel coming out from the rear carb exit.

Root cause suggestion:
Vacuum lines to the pump
Pump not working due to ethanol attak on the membrane.

After this I have put everything back together, fuelled up with BP ultimate.
The bike sort of runs, but as said, there Fuel/Air ratio on the front cylinder is way out 2+1/4 out.

Next steps:
Clean carb with Sea Foam (can one get his stuff in NL?)
Clean carb with cleaner
Inspect vacuum pump (how to remove ? )
Replace vacuum hose to the pump

Hope for the best 😊

Offline ErTussenDoor

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Re: VX800 Scrambler
« Reply #11 on: July 10, 2018, 04:31:57 AM »
If you disconnect the fuel line at the front carb and crank the engine, is there fuel coming out of the fuel line if you sort of hold it in the same position near the carb?

Offline Michael Star

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Re: VX800 Scrambler
« Reply #12 on: July 10, 2018, 04:44:33 AM »
Hi Andre,
yesterday it was not. No fuel came out.

I had fuel in the fuel line, fuel line was disconnected from the tank and elevated above the front carb.

So it should work, but nothing. no fuel coming out.

Offline ErTussenDoor

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Re: VX800 Scrambler
« Reply #13 on: July 10, 2018, 05:01:04 AM »
So then it is either the vacuum hose or the fuel pump itself. Carb cleaner won't help much I am afraid

Offline Michael Star

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Re: VX800 Scrambler
« Reply #14 on: July 10, 2018, 08:04:55 AM »
Exactly my thought.
Any idea how to best get tot he fuel pump?
From the top:
Remove battery and battery compartment or

from the front?
removal or rear air filter assembly?

 

anything