[Nate90]

Rebuilding the engine and the last thing we need to solve is the carb. We can't repair it and we can't buy replacement parts for it. So my question is what's an alternative carb to use?

[Chief_Mechanic]

Rebuilding the engine and the last thing we need to solve is the carb. We can't repair it and we can't buy replacement parts for it. So my question is what's an alternative carb to use?

What replacement parts are you unable to get?  I haven’t had any problems so far, but I haven’t done a full carb rebuild.  I’ve seen others in the Facebook group who rebuilt their carbs ordering through their local Yamaha dealers.

Let me know what you are having trouble finding and I’ll help you look for alternatives or see if they’re available here in Japan.

[Nate90]

I live in Vietnam and it was a grey import here, so parts are incredibly hard to find and it's illegal to bring in second hand vehicle parts here. So yeah please man that would be massive help. Shoot me an email [email protected]

[Chief_Mechanic]

Okay, found this on this page:http://blog.livedoor.jp/lion1012/archives/1821117.html
(English translation below)


ＦＣＲ28ダウンドラフトタイプ　装着には、　かなりの加工やパーツ交換が必要になります。

まず、ノーマルはツインキャブですが、　ＦＣＲは本体がかなり大きいのでツインキャブにできたとしてもタンク下に装着スペースが確保できません。

そこでシングルキャブを選択となり、ビラーゴ250の１in２　の純正マニホールドを入手（ネットで安価なコピー品？を入手しましたが、マニホールド内部の通路がスムーズではないので却下）。

マニホールド装着となるがエンジン側で短すぎて装着できない！

ビラーゴのシリンダーヘッドを調べると吸気マニホールド部がルネッサ（４ＤＮ）より突出しているのだ。

マニホールドはスペーサー製作でどうにか着くようだが、今回はビラーゴのシリンダーヘッドを使用して装着となった。

その他、ビラーゴのマニホールドに合わせキャブレターのスピゴットを製作。

ノーマルのスロットルワイヤーでは装着できないので社外品のハイスロＫＩＴを使用。

後部シリンダーヘッドの左側カバーに干渉するのでカバーを少しカット。

ノーマルのエアクリーナーは当然使用できないのでパワーフィルターを使用。

などなど、ＦＣＲ装着はかなりハードルが高いのです。

ちなみに装着後は、燃費はノーマルと変わらず、吹け上がりとトルクの盛り上がりはサイコー！！
となるのです。

The FCR28 downdraft type carb requires a lot of modification and parts replacement.

First of all, the standard SRV is a twin carburetor, but the FCR is quite large, so even if it can be made to fit, there is no space under the tank for installation. (Unless you use pod intake filters)

So, I decided to go with a single carb, and obtained a 1-in-2 stock manifold for the Virago 250 (a cheap copy on the Internet?). But I rejected it because the passage inside the manifold was not smooth.

The manifold would fit, but it was too short on the engine side to fit!

When I examined the cylinder head of the Virago, I found that the intake manifold part protrudes more than the Renessa (4DN).

The manifold can be installed by making spacers, but this time we had to use the Virago cylinder head.

I also made a spigot for the carburetor to fit the manifold of the Virago.

Since the stock throttle wire cannot be used, an external high throttle KIT was used.

Cut off the left side cover of the rear cylinder head.

The stock air cleaner cannot be used, so a power filter was used.

The FCR installation is a very difficult task.

By the way, after the installation, the fuel consumption is the same as stock, but the boost and torque is awesome!
The fuel economy is the same as stock, but the boost and torque is amazing!