Help!! Keep breaking reed petals in a TS1

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Mark 1
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Tue Jun 26, 2018 2:11 pm

Any ideas appreciated before I set fire to this scooter... :x

I’ve just destroyed either the 4th or 5th set of reeds in a year, I’ve lost track! I haven’t even taken the reed block off this time, I just know what the problem is :cry:

TS1 with MB Race Tour tune it’s been on two different engines, one with a 58/110 crank the other a 60/110. I’ve had three different exhausts on it, all expansion types, and always with a TMX35. Standard reed block and vetronite petals.

First time a definite back fire did it, not noticed one since. Twice the petal has had a chunk blown out the middle (this stops the scooter dead) twice the petal has had fraying at the bottom or little bits of the corners; runs like this just very rich. Definitely five sets then because I haven’t checked this occurrence.

Pretty sure no electrical issues and backfire, apart from the first time. Squish is quite low on current engine from memory about 1.13, could this be a factor? :?

What about solutions? Can you double up reed petals on a TS1? Would a reed stuffer/packer help? I looked at V Force reviews and think the reeds may be even weaker. The BGM Yamaha reeds look less brittle but you need a 3mm packer with the block and I don’t have that spare under the frame.

Thanks Mark

hendy
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Tue Jun 26, 2018 9:04 pm

Maybe use a reed packer and take a bit of metal off the top of the manifold? That's what I did with standard cones and s3 rear shock. That was with bgm/Yamaha reed block and mb manifold

Mark 1
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Tue Jun 26, 2018 10:29 pm

Hi Hendy,
How much can you take of the top of the manifold, safely, about a mill, less?
My thought on the packer was it may reduce blow bag from any misfire.

Cheers

Mark 1
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Tue Jun 26, 2018 10:31 pm

Apologies meant ‘blow back’ :D

hendy
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Wed Jun 27, 2018 12:44 pm

I took at least 2mm from the top of mine. The one I had on my last motor, a gt186, was the same despite exiting on the normal side.

Mark 1
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Wed Jun 27, 2018 5:50 pm

Thanks I’ll give it a go at the weekend, I have spare manifold so can afford to get it wrong once :o

I will also be rechecking everything as don’t want to hide the real problem.

Cheers

Mrnice71
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Thu Jun 28, 2018 4:24 pm

Strange one this .... l ran a TS1 for several years & never had reed petal issues , my set up was a standard reed block standard reeds , reed stops modified slightly , 3mm packer & MB manifold for extra clearance but did need to use taffy longer shock to achieve this and to stop taffy pipe banging on rear runner bracket . Hope this helps .

Mark 1
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Thu Jun 28, 2018 7:39 pm

Thanks for the idea Mrnice,
I think the clearance issue will be with the back bolt with the shallow head rather than the manifold itself so a longer shock may help. But, how far to go, new shock, reed block, packer, even try the LTH manifold. All hard earned pennies when there is possibly some underlying problem. Someone on the other forum broke two sets and turned out to be a dodgy plug, so could be simple :? I hope!!

Interesting you had a 3mm packer with a standard reed block and altered the stops. Was that recommended by someone? Especially as you had no issues. I look at the stops on the bgm block and think “they must be there for a reason”.

Cheers
Mark

Muppet
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Thu Jun 28, 2018 8:23 pm

most likely ignition related but it cud be detonation thats popped the reeds
im not a complete idiot
.
.
s me of the piec s are mis i g

Mark 1
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Thu Jun 28, 2018 9:42 pm

I thought wiring muppet, but the kit has been on two engines both with BGM stator, I have resecured the flywheel earth and changed cdi, ht lead and cap. I have not redone the cdi earth (will do tomorrow) or changed plug (also tomorrow).
I ran for a while with the ‘kill switch’ left out of the cdi, not sure if this helped or not though but the two engines used have both been in the same scooter with same wiring and loom, so possibly the cause is in that set up. No back fires since the first failure either :?

Cheers
Mark

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