Author Topic: TGB Laser R9 suddenly died - simple problem  (Read 5931 times)


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TGB Laser R9 suddenly died - simple problem
« on: March 20, 2010, 08:22:08 PM »
I thought that I should share I problem that I recently had with my 151cc TGB scooter.
I have driven my scooter for over 3000 miles without any problem but last week the engine suddenly died while I was cruising along at 40mph.
The starter could still turn the engine over but the engine did not start anymore. After about 20 mins I tried again and the engine started immediately. However, after riding the bike for another mile or so the same problem:
engine suddenly died.
Finally at home I discovered the reason:
There is a breather hose going from the cylinder head cover to an airbox. The airbox is connected to the engine intake and there is another transparent hose from the airbox going down which is terminated with a plug.
Obviously the purpose of the airbox is to ventilate the engine valve compartment and to feed any oil vapor back into the intake so that it can be burned in the engine. But depending on the weather conditions there is also condense water coming from the valve compartment into the airbox and is collected by a sponge in the airbox. Water dripping down from the sponge is collected in the transparent hose but it can't go anywhere from there because there is a plug at the end of the hose.  In my case the entire hose was full of water and water started to accumulate in the airbox and got sucked into the intake. And this caused the engine to die.
As far as I have seen, there isn't anything written anywhere in either the TGB owner manual or service manual that this transparent hose needs to be opened from time to time to empty it.
You should definitely empty this hose from time to time.
Please don't forget to put the plug back into the end of the hose. Otherwise ventilation of the valve compartment will not work properly!


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Re: TGB Laser R9 suddenly died - simple problem
« Reply #1 on: March 21, 2010, 09:01:03 AM »
most GY6 scooters use that system to meet the pollution regs.
there are some after market hose draining kits.
but your right keep your eye on the hose and drain it when
you change the oil  or replace the plug or once a season
or once every 1000 miles...

i own a scooter shop  with rentals ,sales& racing parts.
i also appraise scooters for KBB.

2003 Vino classic stage 0.75
de-reged stock variator w/8g sliding weights.
1.5k rpm  springs
2005 veniceLX ~70cc~upjet~1.5k rpm springs & 7gr sliders
KeyWest de restricted~8gr slide


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Re: TGB Laser R9 suddenly died - simple problem
« Reply #2 on: March 23, 2010, 01:26:34 PM »
I was only surprised that there is nothing mentioned in either the owner manual or service manual.

This is my first scooter and assumed that if I follow the maintenance tasks in the manuals then I should be fine. But obviously there are some things that you have to find out the hard way.

I wonder if there are more things where I should pay attention to and which are also not mentioned in the TGB manual?