Topic: '77 550k carb question

[Jay B]

I brought home my new 550k project bike tonight, and I already have a question. I've read here that this bike has the "emissions" carbs, and I was wondering if there is any benifit to running an earlier set of carbs. If there is I'll try to find a set before I waste time messing with these.

[csendker]

I'm thinking I read somewhere that the Type 1's (earlier) & the PD's (later) are physically slightly different.  Maybe just the manifolds?  I'm not sure the PD's are 'bad' or 'worse', just different.  If it were me, I think I would stick with the correct model.  Now if you're heavily modified, the carbs will have to be dialed into your specific set-up anyway, so the theory crumbles slightly.

[750goes]

heres what your bike should have  -

http://www.motorcycleproject.com/motorcycle/text/specs.html

[TwoTired]

I brought home my new 550k project bike tonight, and I already have a question. I've read here that this bike has the "emissions" carbs, and I was wondering if there is any benifit to running an earlier set of carbs. If there is I'll try to find a set before I waste time messing with these.

These carbs work on the same principles as the older carbs, but have different internal parts.  They respond to changes in the same way as the earlier carbs and have the same throat diameter and breathing characteristics.

Why don't you tell us what your goals for the bike are?  Restoration?  Drag bike?   Full custom?   Or, yet another cafe clone?

[Jay B]

I looked at the chart from 750goes and it seems that the low speed jets are the big difference. If that's the case, I think I'll work with what I have.

TT- I haven't decided yet how I'll set this bike up. When I went to pick it up last night, it was much nicer than I expected, so my options are open. Bought it sight unseen off eBay. I thought I'd get it up and running first then we'll see. I will try and have some pics of it up this evening.