Dt50 hybrid compression?¿

So I made a cool moped, this is a dt50 aircooled cylinder that treatland offers. I made it work on the motorized bike kits. Treatland didn’t have the OEM intake so they sold me some reed cage that fits with modification. I had to space the reed cage to not hit the cylinder with plastic spacer and thick cork gasket. I believe the increase in volume is not making my engine run. I know it has spark and will not start with starting fluid. I was considering 3 reed cages, a stock two petal rd60 reed cage that looks like it’s meant for my cylinder. This treatland reed that shares the same dimensions but has a stuffer and is 4 petal. Or the OEM reed from partzilla.

https://www.ebay.com/itm/182986572862?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D231963%26meid%3D377b9735d5eb41adac2a022a770c1bd7%26pid%3D100935%26rk%3D2%26rkt%3D12%26mehot%3Dpf%26sd%3D283460843411%26itm%3D182986572862%26pmt%3D1%26noa%3D0%26pg%3D2332490%26algv%3DSimplAMLv9PairwiseUnbiasedWeb%26brand%3DYamaha&_trksid=p2332490.c100935.m2460

https://www.treatland.tv/doppler-ER3-4-petal-reed-block-p/doppler-reed-block-gilardoni.htm

https://www.partzilla.com/product/yamaha/53V-13610-00-00?ref=295450ef21e93f483b01f0ba7aec70d1b97171b4

6A7FB091-77D0-448C-94C1-A195FB8488D4.jpeg
5515D831-6DC6-4A4A-8710-20FBFCBD2709.jpeg
14F113BA-940F-4034-892F-AF829EC0F143.jpeg

Re: Dt50 hybrid compression?¿

Dirty30 Dillon /

Have you done a leakdown test? Cork gasket is not meant to really be torqued down like that and the intake looks very crushed.

Re: Dt50 hybrid compression?¿

Hepatitis J [OFMC] /

this is tight

14F113BA-940F-4034-892F-AF829EC0F143.jpeg

Re: Dt50 hybrid compression?¿

Ditch the cork for a better gasket material. Also make a proper mount for the pipe instead of duct tape and please don’t run it with that gas-soaked carb filter resting on the hot stinger of the pipe 🔥

Re: Dt50 hybrid compression?¿

Lol honestly the pipe sits well as is I just use duct tape in case of vibes. When it gets more official I use metal straps it’s just more easier to cut tape during testing..... I’m also using a 24mm dellorto phbl carb running 40 idle jet if that matters. It has a score now although it is not the deepest, but not the lightest ;_;

7A481365-C54C-4330-A948-D86C80CD0386.jpeg
0F730C16-A30A-45A6-8056-FFA532BCDC11.png
5522EB06-09CA-4872-9E44-3DC9292033C1.png

Re: Dt50 hybrid compression?¿

I can ditch the cork and use a stack of 1mm gasket and copper sheet. I used the cork cause it was thick enough to space my reed from hitting my cylinder.

06E3BCF0-12BA-4B17-81D6-E9032B8BD214.png

Re: Dt50 hybrid compression?¿

Dirty30 Dillon /

If the photos are of your compression and TDC piston position, than that's why it won't run.

You fit the cylinder on there, but it's not that right stroke for that engine.

Re: Dt50 hybrid compression?¿

The dt50/rd50 stroke is 39.7, any idea what that bike kit engine is? If you have the name/make you can probably find the stroke length info

Re: Dt50 hybrid compression?¿

It looks like he made a cylinder base spacer, but that bitch is too thick for sure.

Why are you putting all of this work into a bike that the bottom end is going to fail on shortly after you get everything sorted?

Re: Dt50 hybrid compression?¿

Yeah imma just end up buying a 40mm stroke crank, I’m running a short rod 38. Still concerned about my reed though cause I’ve had a similar issue before where a big reed increased too much volume to not run. And thoughts about carb size?

Picture is of reed cage I’m using vs what the intake manifold looks like. I’m using some weird plastic spacer from treatland and thick gasket just so the reed cage doesn’t hit my cylinder

10B5F2B0-6DC4-430E-92BF-1C9D9520D862.jpeg
F75372B3-6765-4F1C-9832-F61F52909878.png

Re: Dt50 hybrid compression?¿

That’s a huge carb for a 70. I typically run a 15 or a 19 on 70 kits but I know folks run bigger sometimes

« Go to Topics — end of thread

Want to post in this forum? We'd love to have you join the discussion, but first:

Login or Create Account