Hobbit proma not hitting pipe unless downhill

Hi guys so I have a standard hobbit paii with lightened weights and proma exhaust. It pulls well with plenty of low and mid range power. She gets from 28- 35mph gradually but I don't really feel like it's hitting the pipe unless I go downhill. I've upjetted as it was running a little lean after the pipe and added new points and gapped the plug properly cleaned the rear drive pulley and ramp plate and added a NOS Mitsubushi belt. The plug is a chocolate brown. Is this an indication that my weights are still too light? Or it just simply doesn't have the power from the cylinder. I'm really contemplating the DR kit, but my second thoughts are that it's pretty reliable now as a stocker and fun just whipping around the streets. Am I being unrealistic to expect much more from my set up?

Cheers , Luke

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Re: Hobbit proma not hitting pipe unless downhill

Lighter weights

What weights are you using?

Re: Hobbit proma not hitting pipe unless downhill

> JBOT Admin Wrote:

> -------------------------------------------------------

> Lighter weights

>

> What weights are you using?

Im using drilled out paii weights, I drilled them to 11g, but felt like any more would not allow the end caps to fit properly. I guess I could still them across the middle but not sure if they would roll anymore.

Re: Hobbit proma not hitting pipe unless downhill

Way too heavy.

You want at most 10g, but lower like 8-9hbis better

Buy or make delrin or nylon weights. (edited)

Re: Hobbit proma not hitting pipe unless downhill

Re: Hobbit proma not hitting pipe unless downhill

> JBOT Admin Wrote:

> -------------------------------------------------------

> Way too heavy.

>

> You want at most 10g, but lower like 8-9hbis better

>

> Buy or make delrin or nylon weights.

Cool thanks! I thought perhaps the lighter weights wouldn't have the velocity to throw the belt up high on the variator and rob the top speed.

Re: Hobbit proma not hitting pipe unless downhill

Shawn Manthey /

When I was playing with the weights in my variator I just kept using lighter and lighter weights until I started to lose top speed.

Re: Hobbit proma not hitting pipe unless downhill

> Shawn Manthey Wrote:

> -------------------------------------------------------

> When I was playing with the weights in my variator I just kept using

> lighter and lighter weights until I started to lose top speed.

Ah cool! Did you gain much top end? What did you end up settling at?

Re: Hobbit proma not hitting pipe unless downhill

the proma has good low to mid pull. if u wanna rev out more you have to port yout ports.

Re: Hobbit proma not hitting pipe unless downhill

Thanks, I think perhaps I expected too much, but have heard great results (38mph+) using the proma pipe with a similar set up. I have been reading around a while at porting and I may eventually give it ago, but it seems a lot to research before I even go near the cylinder. I've seen some port maps, are they the easy way to replicate ports without the need for the mathematical equations?

Re: Hobbit proma not hitting pipe unless downhill

Tweaker trash /

Timing?

Re: Hobbit proma not hitting pipe unless downhill

> Barack Obama Wrote:

> -------------------------------------------------------

> Timing?

I couldn't really retard or advance it too much unless I removed the Woodruff key, but timing (via points gap) is set to 0.38mm. does this sound about right?

Re: Hobbit proma not hitting pipe unless downhill

Ricky Lacapria /

Also You will not regret the DR kit. So good

Re: Hobbit proma not hitting pipe unless downhill

> Ricky Lacapria Wrote:

> -------------------------------------------------------

> Also You will not regret the DR kit. So good

Have you had any issues with over heating at all? How high did you jet? I'm thinking it's got to be within the 90-100 mark?

Re: Hobbit proma not hitting pipe unless downhill

Dirty30 Dillon /

Stock PA50i weights are great for stock+pipe hobbits, ran that with a WE custom pipe and that bikes was a solid 40 mph bike. Clutch springs, as well.

Re: Hobbit proma not hitting pipe unless downhill

> Dirty30 Dillon Wrote:

> -------------------------------------------------------

> Stock PA50i weights are great for stock+pipe hobbits, ran that with a WE

> custom pipe and that bikes was a solid 40 mph bike. Clutch springs, as

> well.

See that's what I thought I would be getting 40mph, but sadly not. I will try lighter weights. I have a NOS set on the way in the mail so if I drill mine out too much I still have a spare set. What springs did you use ? Dio 1.5k? Do you know where I could buy some? Also did you have to get rid of your starter springs?

Re: Hobbit proma not hitting pipe unless downhill

Downhill Harvey (OFMC) /

You really need to invest in a timing light. Timing before jetting.

Re: Hobbit proma not hitting pipe unless downhill

Proma pipe, up-jet and nothing else got my hobbit to 36.

Re: Hobbit proma not hitting pipe unless downhill

I do have a timing light, but didn't realise there was much scope for timing on a hobbit, I will check the timing later and see where it's currently at. Would retarding ignition be more in my favour with my current set up?

Re: Hobbit proma not hitting pipe unless downhill

Shawn Manthey /

> Luke W Wrote:

> -------------------------------------------------------

> > Shawn Manthey Wrote:

>

> > -------------------------------------------------------

>

> > When I was playing with the weights in my variator I just kept using

>

> > lighter and lighter weights until I started to lose top speed.

>

>

>

> Ah cool! Did you gain much top end? What did you end up settling at?

I got an urban express but i ended up with 15 grams in the variator. 3 rollers 5 grams each, with my current setup my top speed is 53. Ive been thinking about dropping weight just a touch more and see what happens.

Re: Hobbit proma not hitting pipe unless downhill

Dirty30 Dillon /

Stock cylinder and a pipe, you don't need to worry about timing. The majority of people have excellent results running stock Ignitions using the fixed stator and key.

I used Dio 1.5k springs and they're great. You can get them literally all over the place.

Don't get rid of the starter shoes unless you have a kick or pull start setup already.

Re: Hobbit proma not hitting pipe unless downhill

> Dirty30 Dillon Wrote:

> -------------------------------------------------------

> Stock cylinder and a pipe, you don't need to worry about timing. The

> majority of people have excellent results running stock Ignitions using

> the fixed stator and key.

>

> I used Dio 1.5k springs and they're great. You can get them literally

> all over the place.

>

> Don't get rid of the starter shoes unless you have a kick or pull start

> setup already.

Thanks man! You dont have a link to them by any chance do you?

Re: Hobbit proma not hitting pipe unless downhill

Pffft. So I drilled out the weights to around 10g now I've lost 3 mph off the top speed. :( The low range is great. Really off the mark now!! Don't know what to do now! In terms of top speed. going to have to strip the engine down I think.

Re: Hobbit proma not hitting pipe unless downhill

What you gain on one end comes off the other end .

Re: Hobbit proma not hitting pipe unless downhill

You should disassemble and clean up your rear pulley.

That's where real speed is attained.

Re: Hobbit proma not hitting pipe unless downhill

My Hobbit with a Proma pipe never did more than 36 on flat even with some minor tweaking elsewhere. Upgraded reeds are a game changer. I'm curious about one thing before I recommend DR. Are you running the stock air filter? If so, pull it and see what happens. Even further no stock filter and then plugging one or 2 of the 3 intake tubes changed the game, I'm not kidding. I'm not completely sure why nor do I care but try it. I just DR'd mine and it's a whole different bike. But...it's a full commit. You could just slap on the kit and hope for the best with the crank etc but it's more like DR plus this that and the other thing, a commitment with labor and money. Was worth it for me. I wouldn't expect to hit 50mph right away with a DR. Mines at 42 but not broke in yet. There are benefits to just being happy with what ya got.

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