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Discussion Starter · #1 · (Edited)
More tips from one of the O.G cag tuners.


Clutch Springs:

Heres another quick fix I tried that works possibly better than the homemade springs. I removed 2mm from the end of the bolt hook on the OEM springs and rebent the hook. I made sure all three springs were of uniform length and reinstalled. A little tough due to shorter length, but it can be done. REsults are similar to homemade springs, but engagement is quicker @ rpms probablu due to more consistent spring length and smaller wire diameter. Again, creates engagement @ hi rpms, DON"T USE FOR GENERAL RIDING! RACING USE ONLY


Throttle slack:

Use your 14mm open end wrench from the chain side of the bike to tighten. Also, if you have slop in your throttle, remove the dust boot off the top of the carb to take out slop. Don't back out too much. You want at least 4 threads in the bonnet. MAke sure you tighten down the lock nut when you're done. It is also a good idea to check the tightness of all your fasteners and locktite if necessary. Oh, one more thing, check sprocket alignment. Didn't on the first one, learned the hard way. Threw and wrapped the chain, I supermanned for about 20 feet.


Carb shimming:
As far as reed block goes, reeds are sandwiched and screwed between stoppers and plate and held to case by four bolts on the corners of the block. Without stopper, reeds would fly into crank, not good. Screwed from outlet side of block. Reed block should just pop off with a little help from a scraper or flat head screwdriver once you remove the four allen bolts. Nothing to mess with unless u want to change petals. But then, you're not production class.

Some of the 2.5 parts do fit. The clutch however, does not. A racing clutch is in development. You can fab springs or trim stock springs and rebend hooks for higher engagement rpm's. IF u trim, about 2-3 mm is all you can trim and not have too hard a time putting them back on. Only recommended for racing as starting and stopping will cause early clutch pad wear. Stronger springs create more slippage until you catch up with engine speed. Another good fix for low/ mid power is to adjust all slack out of throttle cable and shim up carb needle. Remove carb cap(cover on top of carb w/cable going in it)Throttleplate (black cylinder) and needle will come out together. SHims should be made of thin stainless or brass. You can buy shim stock at any hardware store. Cut pieces similar to needle retaining washer and insert below retaining washer. Experiment with thin shims(.005 in.). I wouldn't add more than .010-.015 in. total. Bike motors vary so trial and error is the best method. Also check plug to make sure you're not running too lean or rich. Finally, can the stock air filter and use a med/fine stainless wire mesh or blata 2.5 Hi flow air filter w/ adapter. I've gotten the best gains out of mesh and pantyhose. Way less restriction to air flow. Pipes are a crapshoot, haven't tried the 2.5 racing pipe, but it should bolt up with a little, if any, dremel modifications. Blata 2.5 pinions and Blata 13 elite rear sprockets fit.; I run a 7/70 for long tracks and a 6/70-72 for shorter ones. One other mod which I haven't done is port out the carb. Search for ip2 in the forum. He posted more info on porting.

not really, you may play catchup on hard throttle application, which is a little lag till the jet gets flowing. Quick tip is shim up the needle valve a little. Pull the carb/throttle cap off and remove slide. remove cable/spring and place a thin#6 flat washer underneath the needle valve in the slide and reinstall in reverse order. Will richen u up a little for better low end power with new air filter.


Frank Giannini info
Frank Giannini makes the four petal reed block, DC buys from Frank. PInion is Blata 2.5, sprocket is Blata elite 13, filter is polini, carb is dellorto SHA 14-14, intake is blata 2.5.

Frank has to do the head work. HE machines your barrel(cylinder) and installs a high compression head that has the plug located in the center instead of on the side. Also, having the heah separate allows you to adjust squish(piston to top of cylinder distance) with shims. More squish(smaller space between top of piston at top dead center and head) higher compression, higher compression, more power.

I'm not sure if Frank is getting his own barrels or if you actually have to send him yours. Also check with DC to see if they can have the head work done and possibly set up your engine complete. Yoou would have to send it to them and be out of a ride for a few weeks, though.

As far as gains, you will be close to a polini 4.2-6.2, that range. Ask Frank about Dyno data Remember you still have the stock pipe, and if you get the carb, don't forget a jet set say from # 68-74, because as you do additional mods, air/fuel mixture will change resulting in lean/rich mixtures.
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