T5 problems

My T5 runs OK round town, and pulls OK. I have a problem with it cutting out if I have a sustained burst, say 3 minutes at 45mph. Then it cuts out under deceleration, otherwise seems ok.

What could be causing this?

Also I have seen nention of using gasket sealer on the barrel base gasket, is this recommended?


Hiya Chaps,
all 172 kits have that sh** pinging sound, on the original barrel there are several black rubber pads, take them off and put them on the fins of the malossi barrel and it should ease the noise[:dance1:]

the walls of the casings around the base gasket around the ports is quite a thin edge.with heat expansion in the motor this thinner casting can expand and contract at a greater level than a thicker cast and so is prone to opening small gaps to leak air causing a leaner mix and overheating usually found after local running regularly and then a good blast like a rally journey where they expand beyond the norm .always a good idea to give the gasket a thin smear on non silicone sealer to safeguard

I should mention that the cutting out thing seems to have disappeared now, don’t know what it was but if it’s gone it’s gone! I did re-adjust a few things so maybe I caught whatever.

Thanks again.


Shouldn’t you be in Iraq with Stu and Paul tidying up for the ragheads?

Yeah probably 4-5 of us, you’re welcome to ride down with us if you go on Saturday morning, are you doing the Cumby this weekend, its worth a look and just on the doorstep, guaranteed good night on Saturday.

Yeah, I decided to just run it anyway and it seems to go OK, I done 250 miles now so opened it up cos I could not resist and got 70 which is good when you consider the throttle cable is fooked so that is about half throttle.

Thanks for all your help


Re: The noise

The 172 Kit is just plain noisy @ tick-over (not like the original)…It’s quite normal , although sounds odd/wrong. (I needed some convincing, Taffspeed gave it) . It should go away @ high rpm…if it does not then check bearings clutch etc.

Micheal KnB,
sorry mate, Stu and Paul are over there picking up my brass from the actual war bit!
Are any of your lot doing Cleethorpes?[:drink:]

the bevelled edge side of the gear normally goes on the outside nearest the clutch,the noise which sounds like the piston hitting the head may just be a b***ing head or a bit of pinking,you can put a thin film of sealer on the head to stop that too.blue hermatite is better than red because it stays sticky and doesnt dry so you get a better longevity of seal

Thanks vespadoctor,

I think I understand what you are saying…not too clever when it comes to this stuff yet.

To put it into my words I think you are suggesting I should take the cyl back off and put some red hermatite type goo on the gasket. (not blue hylomar type).

The other thing I have noticed is since I put the 172 on there is a noise which sounds like the piston hitting the head, but isn’t as I have had it off a few times to check and I had the head machined for squish etc. Is this normal?

Being a pain now but…when I put the autolube drive back on the crank I noticed one side has a bevelled edge, I guessed the bevel went towards the main drive bearings, was I right? (or an I**** as usual!).

Cheers, all help is appreciated.

Hi there i have had two malossi kits in my T5 and they both made a rattleing noise even though both flywheel and clutch bearings were new i guess that is how they are the scooter still runs ok Gary[:dance3:] [:drink:] [:drink:] [:drink:]

3 of us riding down on Fridayso see ya when you get there.
Not sure about Cumby, got to sort me mini out for MOT.
AFSC Catterick.
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