×
Pictures Posting Not Working (12 Jun 2023)
Picture uploads is again unavailable. We are working on the problem. Thanks for your patience.
Makotosun
Porting a 1975 YT 175
- RacerClam
-
Topic Author
- Offline
- Platinum Member
-
Porting a 1975 YT 175 was created by RacerClam
I'm currently porting a TY 175 for a customer who competes in vintage trials. But the problem for him is that it performed like a moped without pedals. So I have done much work to help with that problem including installing a case port that will dramatically improve the snap he desires , along with exaust port , boost port and transfer port mods. It looks racy but the timing is mild. Also will be installing a 28mm VM carb with 6 venture dividers and a ufo.
Rich
Rich
racerclam
The following user(s) Liked this Post: FrankC
14 Jul 2016 14:00
#1
This message has attachments images.
Please log in or register to see it.
Please Log in or Create an account to join the conversation.
- RacerClam
-
Topic Author
- Offline
- Platinum Member
-
The following user(s) Liked this Post: FrankC
14 Jul 2016 14:02
#2
This message has attachments images.
Please log in or register to see it.
Please Log in or Create an account to join the conversation.
- RacerClam
-
Topic Author
- Offline
- Platinum Member
-
Replied by RacerClam on topic Porting a 1975 YT 175
Big oops! I titled it a YT not a TY Forgive me
Rich
Rich
racerclam
The following user(s) Liked this Post: FrankC
14 Jul 2016 14:04
#3
Please Log in or Create an account to join the conversation.
- RT325
-
- Offline
- Platinum Member
-
- Posts: 10461
- Likes received: 4399
Replied by RT325 on topic Porting a 1975 YT 175
yeah YT--3 wheeler-- had me worried as they're dangerous enough in std trim. TY--i have a TY cylinder on my old AT1 piston port 125. Think i have a base plate under it due to conrod length & couldn't be bothered changing it. In fact the bottom end has never been apart since new. Anyway--TY top end goes very much better on this than as a trials bike possibly due to the trail exhaust & 28 carb & has 'willing' top end & over-rev. AT1 pipe i gutted about 35 years ago when it got choked up. Very interesting looking at porting changes from people that know what the're doing!! & thanks for posting. Hope he has a clean exhaust even if it's a std TY pipe--exhaust & tail pipe muffler especially the spark arrestor bit down the end.
The following user(s) Liked this Post: FrankC
14 Jul 2016 15:57
#4
Please Log in or Create an account to join the conversation.
- FrankC
-
- Offline
- Solution Contributor
-
- Posts: 1186
- Likes received: 374
Replied by FrankC on topic Porting a 1975 YT 175
Exemplary work Rich.

The following user(s) Liked this Post: RacerClam
14 Jul 2016 18:02
#5
Please Log in or Create an account to join the conversation.
- RacerClam
-
Topic Author
- Offline
- Platinum Member
-
- Bigpumpingunit
-
- Offline
- New Member
-
- Posts: 1
- Likes received: 0
Replied by Bigpumpingunit on topic Porting a 1975 YT 175
How did this turn out?
Were the porting modifications suited to trials riding?
Were the porting modifications suited to trials riding?
22 Feb 2021 18:08
#7
Please Log in or Create an account to join the conversation.
- RacerClam
-
Topic Author
- Offline
- Platinum Member
-
Replied by RacerClam on topic Porting a 1975 YT 175
Turned out gerat ! Very suited for trials . He competes in vintage trials. I can port for any application.
Rich
Rich
racerclam
The following user(s) Liked this Post: Snglsmkr
23 Feb 2021 12:11
#8
Please Log in or Create an account to join the conversation.
-
- Visitor
-
Replied by on topic Porting a 1975 YT 175
The transfer ducts are very restrictive on TYs. Case port is one way to improve things, but scalloping the liner, adjacent to the A transfer entries, is easier to do. If you can find a DT175 443 cylinder, with slight modification a V Force YZ85 reed block will fit, and in conjunction with a 26mm carb and bigger air box, will mean a 175 which runs as well as a Fantic.
24 Apr 2023 09:00
#9
Please Log in or Create an account to join the conversation.
- Schu
-
- Offline
- Site Supporter
-
- Posts: 1501
- Likes received: 1827
Replied by Schu on topic Porting a 1975 YT 175
Hey Rich,
Just curious. Did your TY porting customer also have you do venturi dividers on his Hodaka? And is he from Georgia?
Just curious. Did your TY porting customer also have you do venturi dividers on his Hodaka? And is he from Georgia?
Schu
CT1B, CT1C, JT1, JT2, CT2, DT360A, GT80B, DT100B, DT125B, DT175B, DT175C, DT250B, DT400B, Z50, SCR950
Someday, you'll own some Yamahas
CT1B, CT1C, JT1, JT2, CT2, DT360A, GT80B, DT100B, DT125B, DT175B, DT175C, DT250B, DT400B, Z50, SCR950
Someday, you'll own some Yamahas
24 Apr 2023 15:32
#10
Please Log in or Create an account to join the conversation.
Moderators: yamadmin, Makotosun, DEET, Vinnie, James Hart