rc pete

iTrader: (6)

Oh, you have the Tessmann 110% XZ-B kit. Yes, in that case the rod will fit both the B2103 and the B21 Ty2.
The XZ-B has multiple versions. The original Speed and Speed Spec 2 had longer rods, non-speed Version 2, the Speed Spec 3 and the Ty 110% has the shorter rod, same as all of the other recent engines.

jersey

iTrader: (1)

Wonder if os coming out with some new tessman model engines wjth updated carb balls and heads etc. they discontinued the ty 110% spec 2 and b21 ty2 engine last week. Or another thought will he switch to Fx engine?

Loua28

Another question, should I use the B2103 crank & head button on my rebuild or use the B2101 TY crank instead? What will the difference be if I'm able to use the B2101 TY crank in the B2103 casing?

Loua28

Jersey, I'm getting my popcorn ready to see what happens...

rc pete

iTrader: (6)

In the B2103 definitely use the B2103 crank. That crank will achieve the required 16.8mm stoke. The Ty2 crank will only provide a 16.4mm stroke, which will not match up with rest of the engine.

Ofna2005

What os based motor best compares to the spec 3 motor ? I have been waiting hoping they would release a new model but haven’t seen anything on the horizon.

SkippyMatt

iTrader: (1)

I don't think they have anything out there that is the spec 3(could be wrong). The closest thing I think would be the new Blok buggy motor, spec 2 internals with spec 3 case.

stephen_bess

They did away w/the Spec III b/c it didn't fill a need - it didn't have the grunt of the Spec II/Tessmann 110% engine, nor did it have the linearity and good mileage of the 2101 or new 2103. The newest OS engines are the 2103 type R and type S, and the Ronda Drake AD2.

Ofna2005

Where can I get spec3 case from ? Mines leak right around carb area the warmer the motor gets the more the rpms go up . I tried sealing it, that was a temporary fix .

stephen_bess

Try eBay. If not there, Tower Hobbies but it'll be full retail.

jersey

iTrader: (1)

maybe you you need new gaskets. Get a new insulator piece for the carb throat and a new oring and that might do it.

if that don’t work I heard the tekno BM case is a spec 3 case. I’m not 100 percent but was told that from a couple people.
https://www.teknorc.com/shop/tkr1724-crankcase-21bm/

but yea they discontinued the os spec 3 so os says sometimes they only manufacture parts till a year after it gets discontinued sometimes. Last time I looked for a spec 3 case couldn’t find them so tekno case MAy be the only route. I’d try the insulator and gasket first.

inlinesick

iTrader: (1)

Samurai S03 and R03 are specs III based! B2103 case and oring head button.

maximax

Hi everybody , I would like to know what do you use to glue thermo insulator on 21J carb??? Or if you don't glue it??

Bigv

iTrader: (3)

The lrp zz21 long stroke David angaro is a spec 2 if this helps

stephen_bess

I've used a dab of CA glue just to secure it. The pinch bolt secures the entire assembly.