Alright lads, was wondering if anyone on here has tried replacing the RB exhaust manifold (the ones that have the 2 rubber O rings) for the TS1 type?
i have tried it after getting pissed off with the pipe always blowing at the manifold, apart from the bloody noise it covers everything under the engine in crap! and of course the biggest factor that the bike would be running lean with a leaking exhaust.
reason i ask is id be intrested in how your bikes ran after?
basicacally my RB20 isnt running like it did, coughing and spluttering till the revs kick in and sometimes even after! and im just working my way through possible causes and any changes ive made, im 80% sure its just the carb needs re-jetting but want to look at other causes too, would be worth having a look at the reeds as well id have thought?
cheers, John.
oh, and who elses tailcan de-rivets itself and falls off! i re=rivet it every bloody week!
franspeed JL3- changing and RB manifold to TS1 type
- northyorksaint
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Yeah, had roughly the same thing mate. Changed the stub and found it had to be leaned off in the midrange. Must have been drawing air from the off ( bought the pipe 2nd hand).
- northyorksaint
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thanks for your reply mate, im also considering getting an outer sleeve welded to the original RB stub wide enough so that the exhaust has a bit of free movement and not tight like it is with the TS1 stub.
You might want to check that there is room for the nuts to go on before you weld the sleeve on. I had to grind the sleeve and file down the nuts n washers.
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I have an RB20 with the same issues. I have changed the slide cleaned the carb and still the same. I have an avanti head on now and this may be part of the problem with the head now running cooler. I'm going to try a b7 firs.t then the atomiser and main jet. if it's still an issue I'll look at the Augusto. this will mean running it down to jb to be dynoed though.northyorksaint wrote:Alright lads, was wondering if anyone on here has tried replacing the RB exhaust manifold (the ones that have the 2 rubber O rings) for the TS1 type?
i have tried it after getting pissed off with the pipe always blowing at the manifold, apart from the bloody noise it covers everything under the engine in crap! and of course the biggest factor that the bike would be running lean with a leaking exhaust.
reason i ask is id be intrested in how your bikes ran after?
basicacally my RB20 isnt running like it did, coughing and spluttering till the revs kick in and sometimes even after! and im just working my way through possible causes and any changes ive made, im 80% sure its just the carb needs re-jetting but want to look at other causes too, would be worth having a look at the reeds as well id have thought?
cheers, John.
oh, and who elses tailcan de-rivets itself and falls off! i re=rivet it every bloody week!
O
H and I replace rivets on my Franspeed race every couple of months. also get it welded every few months as well. must have been welded seven times, come to think of it it's being welded at the moment

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I have an RB20 with the same issues. I have changed the slide cleaned the carb and still the same. I have an avanti head on now and this may be part of the problem with the head now running cooler. I'm going to try a b7 firs.t then the atomiser and main jet. if it's still an issue I'll look at the Augusto. this will mean running it down to jb to be dynoed though.northyorksaint wrote:Alright lads, was wondering if anyone on here has tried replacing the RB exhaust manifold (the ones that have the 2 rubber O rings) for the TS1 type?
i have tried it after getting pissed off with the pipe always blowing at the manifold, apart from the bloody noise it covers everything under the engine in crap! and of course the biggest factor that the bike would be running lean with a leaking exhaust.
reason i ask is id be intrested in how your bikes ran after?
basicacally my RB20 isnt running like it did, coughing and spluttering till the revs kick in and sometimes even after! and im just working my way through possible causes and any changes ive made, im 80% sure its just the carb needs re-jetting but want to look at other causes too, would be worth having a look at the reeds as well id have thought?
cheers, John.
oh, and who elses tailcan de-rivets itself and falls off! i re=rivet it every bloody week!
O
H and I replace rivets on my Franspeed race every couple of months. also get it welded every few months as well. must have been welded seven times, come to think of it it's being welded at the moment

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Are you using steel or aluminium rivets?
You can get rivets where the mandrel (the bit that snaps off when you set them) snaps off flush at the top of the rivet, making the job much stronger. Especially steel ones. Bit more of a bugger to drill out though.
Use rivets which are the correct length for the thickness of material being joined.
You will likely need something stronger than a set of hand setting pliers though if you use the 4.8mm steel ones.
Once the holes have been enlarged, soft ally rivets tend to fret around and shear off ever faster. Especially cheap shitty ones where the mandrel head falls out after setting.
Could you re-drill? If so make sure you use the correct size drill, and remove any burrs which may prevent a tight fit up.
Sounds like the joint is at a vibration node.
You can get rivets where the mandrel (the bit that snaps off when you set them) snaps off flush at the top of the rivet, making the job much stronger. Especially steel ones. Bit more of a bugger to drill out though.
Use rivets which are the correct length for the thickness of material being joined.
You will likely need something stronger than a set of hand setting pliers though if you use the 4.8mm steel ones.
Once the holes have been enlarged, soft ally rivets tend to fret around and shear off ever faster. Especially cheap shitty ones where the mandrel head falls out after setting.
Could you re-drill? If so make sure you use the correct size drill, and remove any burrs which may prevent a tight fit up.
Sounds like the joint is at a vibration node.
- northyorksaint
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sydduckett wrote:I have an RB20 with the same issues. I have changed the slide cleaned the carb and still the same. I have an avanti head on now and this may be part of the problem with the head now running cooler. I'm going to try a b7 firs.t then the atomiser and main jet. if it's still an issue I'll look at the Augusto. this will mean running it down to jb to be dynoed though.northyorksaint wrote:Alright lads, was wondering if anyone on here has tried replacing the RB exhaust manifold (the ones that have the 2 rubber O rings) for the TS1 type?
i have tried it after getting pissed off with the pipe always blowing at the manifold, apart from the bloody noise it covers everything under the engine in crap! and of course the biggest factor that the bike would be running lean with a leaking exhaust.
reason i ask is id be intrested in how your bikes ran after?
basicacally my RB20 isnt running like it did, coughing and spluttering till the revs kick in and sometimes even after! and im just working my way through possible causes and any changes ive made, im 80% sure its just the carb needs re-jetting but want to look at other causes too, would be worth having a look at the reeds as well id have thought?
cheers, John.
oh, and who elses tailcan de-rivets itself and falls off! i re=rivet it every bloody week!
O
H and I replace rivets on my Franspeed race every couple of months. also get it welded every few months as well. must have been welded seven times, come to think of it it's being welded at the moment
thanks for your reply mate, i took the TS1 stub off and trimmed it down as it was a bit too long for the exhaust to sit correctly on the bracket, thought maybe doing this small change might have helped but no.
i replaced the carb rubber which was looking worn for the AF stepped rubber, this cured the problem for a couple of days but went back to coughing and spluttering this morning on my way back from brid, ive 2 roads to go down now imo, i drop the engine out and check and replace all the seals and gaskets between the carb manifold through to the exhaust manifold as it was suggested that an airleak, even a small one, can cause it it run like this?
and the other road is getting it on the dyno and check the jetting, it could even be as simple as a worn atomiser!
and in relation to the JL3 tailcan, i got so sick of the rivets i had mine welded up as well, only been done a week so suppose its a case of waiting to see if it holds or not!
- drunkmunkey6969
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John.... Ring me after 12pm one day this week and we'll get you on the Dyno.....it's only £35 for the initial diagnostic run, and then we can find out what it actually needs......that's gotta be a better idea than stripping your engine if you don't need to? 

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